1001

App history

Tab added to Task Manager in Windows 8 to collect stats such as CPU time and network usage on programs that have run recently.

Preboot Execution Environment (PXE)

Technology that enables a PC to boot without any local storage by retrieving an OS from a server over a network.

Global Positioning System (GPS)

Technology that enables a mobile device to determine where you are on a map.

byte

Unit of 8 bits; fundamental data unit of personal computers. Storing the equivalent of one character, the byte is also the basic unit of measurement for computer storage.

joule

Unit of energy describing (in this book) how much energy a surge suppressor can handle before it fails

spam

Unsolicited e-mails from both legitimate businesses and scammers that account for a huge percentage of traffic on the Internet

SuperSpeed USB 10 Gbps

Updated form of SuperSpeed USB providing speeds up to 10 Gbps. Also called 3.1

print to PDF

Using a virtual printer that produces a PDF file you can save, instead of sending the document to a physical printer

Geofencing

Using mobile device features to detect when the device enters or exits a defined area

Social Engineering

Using or manipulating people inside the networking environment to gain access to that network from the outside.

802.11ac

Wireless networking standard that operates in the 5-GHz band and uses multiple in/multiple out (MIMO) and multi user MIMO (MU-MIMO) to achieve a theoretical maximum throughput of 1+ Gbps

image file

Bit-by-bit image of data to be burned on CD or DVD—from one file to an entire disc—stored as a single file on a hard drive. Particularly handy when copying from CD to CD or DVD to DVD.

sprite

Bitmapped graphic such as a BMP file used by early 3-D games to create the 3-D world.

BD-ROM (Blu-ray Disc-Read Only Media)

Blu-ray Disc equivalent of a DVDROM or CD-ROM. (See Blu-ray Disc.)

BD-RE (Blu-ray Disc-REwritable)

Blu-ray Disc equivalent of the rewritable DVD, allows writing and rewriting several times on the same BD. (See Blu-ray Disc.)

BD-R (Blu-ray Disc-Recordable)

Blu-ray Disc format that enables writing data to blank discs.

dxdiag (DirectX Diagnostics Tool)

Diagnostic tool for getting information about and testing a computer's DirectX version.

Contrast ratio

Difference in intensity between the lightest and the darkest spot that a device can display (in the case of a monitor) or capture (in the case of a camera or scanner)

resistance

Difficulty in making electricity flow through a material measured in ohms

general protection fault (GPF)

Error code usually seen when separate active programs conflict on resources or data. Can cause an application to crash

FAT32

File allocation table that uses 32 bits to address and index clusters. Commonly used with USB flash-media drives and versions of Windows prior to XP.

read-only attribute

File attribute that does not allow a file to be altered or modified. Helpful when protecting system files that should not be edited.

hidden attribute

File attribute that, when used, does not allow the dir command to show a file.

container file

File containing two or more separate, compressed tracks, typically an audio track and a moving-picture track. Also known as a wrapper

WAV

File format for audio faithfully recorded using the pulse code modulation (PCM) format; produces large file sizes

autorun.inf

File included on some media. Lists which program or installation routine Autorun should run

ext4 (Fourth Extended File System)

File system used by most Linux distributions

transmit beamforming

Multiple-antenna technology that adjusts signal when clients are discovered to optimize quality and minimize dead spots. Used in many 802.11n WAPs

polygons

Multisided shapes used in 3-D rendering of objects. In computers, video cards draw large numbers of triangles and connect them to form polygons.

pinch

Multitouch gesture that enables you to make an image bigger or smaller.

CSMA/CD (Carrier Sense Multiple Access/Collision Detection)

Networking scheme used by Ethernet devices to transmit data and resend data after detection of data collisions

Trojan horse

Program that does something other than what the user who runs the program thinks it will do. Used to disguise malicious code.

App Scanner

Program that scans apps installed on a device to highlight risks posed by apps what actions they have permission to take

rootkit

Program that takes advantage of very low-level functionality to gain privileged system access and hide itself from all but the most aggressive anti-malware tools. Can strike operating systems, hypervisors, and even device firmware

device driver

Program used by the operating system to control communications between the computer and peripherals.

Registry Editor

Program used to edit the Windows Registry.

regedit.exe

Program used to edit the Windows Registry.

Cell Tower Analyzer

Program, app, or device to scan and analyze the properties of nearby cellular signals. Can be used to diagnose signal quality issues or identify security threats such as tower spoofing

Wi-Fi analyzer

Program, app, or device used to scan and analyze the properties of nearby Wi-Fi signals. Can be used to identify dead spots, avoid interference from other networks, or identify security threats such as illegitimate wireless access points (WAPs) and more

software token

Programming (usually running on a general computing device such as a smartphone or portable computer) that enables the device to serve as an authentication factor when logging into a secure resource

bug

Programming error that causes a program or a computer system to perform erratically, produce incorrect results, or crash. The term was coined when a real bug was found in one of the circuits of one of the first ENIAC computers.

PAN (Personal Area Network)

Small wireless network created with Bluetooth technology and intended to link computers and other peripheral devices.

gestures

Specific motions the user performs on a touchscreen, such as pinching or swiping, that have a special meaning to the app being used.

file permission

Specifies what degree of access the system should grant a user or group to a particular file

folder permission

Specifies what degree of access the system should grant a user or group to a particular folder

system bus speed

Speed at which the CPU and the rest of the PC operates; set by the system crystal.

ppm (pages per minute)

Speed of a printer.

Pretty Good Privacy (PGP)

Standard for sending and reviving e-mail encrypted to obscure its message from anyone without the key to decrypt it

form factor

Standard for the physical organization of motherboard components and motherboard size. Most common form factors are ATX, microATX, and Mini-ITX.

RS-232

Standard port recommended by the Electronics Industry Association (EIA) for serial devices.

dipole antennas

Standard straight-wire antennas that provide the most omnidirectional function.

MSDS (Material Safety Data Sheet)

Standardized form that provides detailed information about potential environmental hazards and proper disposal methods associated with various computing components.

mSATA

Standardized smaller SATA form factor for use in portable devices

Qi

Standardized wireless charging technology

msinfo32 (system information tool)

Provides information about hardware resources, components, and the software environment. Also known as System Information

DirectX

Set of APIs enabling programs to control multimedia, such as sound, video, and graphics. Used in Windows Vista to draw the Aero desktop.

scripting language

Set of commands, syntax, variables, and format for scripts to be used in a specific computer environment. For example, bash is a scripting language often used in the Bash shell, which is common UNIX environments

maintenance kit

Set of commonly replaced printer components provided by many manufacturers.

script

Set of text instructions that tells a computer a series of commands to execute in a repeatable fashion

expansion bus

Set of wires going to the CPU, governed by the expansion bus crystal, directly connected to expansion slots of varying types (PCI, AGP, PCIe, etc.).

boot options

Settings in the system setup program that define which devices the system will attempt to boot from (and in what order)

user profiles

Settings that correspond to a specific user account and may follow users regardless of the computers where they log on. These settings enable the user to have customized environment and security settings.

imaging process

Seven-step process in laser printing. While it can vary by printer, the steps are typically: processing, charging, exposing, developing, transferring, fusing, and cleaning

Broadcast Domain

group of computers connected by one or more switches-- that is, a group of computers that receive broadcast frames from each other

partition boot sector

sector of a partition that stores information important to its partition, such as the location of the OS boot files. Responsible for loading the OS on a partition

application programming interface

see API

CAD/CAM design workstation

see graphics workstation

update

see patch

Factory Recovery Partition

see recovery partition

activation (virus)

see virus

algorithm

set of rules for solving a problem in a given number of steps (recipe)

Digitizer (Screen)

the touchscreen overlay technology that converts finger and stylus contact into input data for the device to use

decypt

to pass decryption keys and encrypted data through the appropriate decryption algorithm in order to retrieve the original unencrypted data. see encryption

Certificate Authority (CA)

trusted entity that signs digital certificates to guarantee that the certificate was signed by the web site in question (and not forged)

SC

type of fiber optic connector

ST

type of fiber optic connector

DDR3U

ultra-low-voltage version of DDR3, runs at 1.25 V.

drive-by download

undesired file downloads generated by turpid web sites and ads

amperes (Amps or A)

unit of measure for amperage, or electrical current

decibel

unit of measurement typically associated with sound. The higher the number of decibels, the louder the sound

in-place upgrade

upgrade installation

AGP (Accelerated Graphics Port)

A 32/64-bit expansion slot designed by Intel specifically for video that ran at 66 MHz and yielded a throughput of at least 254 Mbps. Later versions (2x, 4x, 8x) gave substantially higher throughput

API (Application Programming Interface)

A Library of related commands available for programmers to use. OpenGL and DirectX, for example, are two well-known 3-D graphics APIs that make it easier to build 3-D games.

air filter mask

A mask designed to keep users from inhaling particulate matter, as when cutting drywall

APM (Advanced Power Management)

BIOS routines (developed by Intel in 1992 and upgraded over time) that enable the CPU to turn on and off selected peripherals. In 1996, APM was supplanted by Advanced Configuration and Power Interface (ACPI).

Anti static bag

Bag made of anti static plastic into which electronics are placed for temporary or long-term storage. Used to protect components from electrostatic discharge

amerage

See current

4G

The fourth generation of cellular data technologies. Most popularly implemented as Long Term Evolution (LTE), a wireless data standard with theoretical download speeds of 1 Gbps and upload speeds of 100 Mbps.

110 block

The most common connection used with structured cabling , connecting horizontal cable runs with patch panels

3G

Third-generation cellular data technologies (such as EV-DO, UTMS, HSPA+, and HSDPA) with real-world speeds under 10 Mbps

AR headset

A non-immersive headset (such as a set of glasses) that places an interface between the wearer and the world. See also augmented reality

Action Center

A one-page aggregation of event messages, warnings, and maintenance messages in windows 7

Account Recovery

A process enabling users to regain account access, typically by resetting a lost or forgotten password

app

A program for a tablet or smartphone. Also, a program written for the Windows 8 Metro interface.

ATA (AT Attachment)

A series of hard drive standards both the older parallel ATA (PATA) and modern serial ATA (SATA) drives. See also PATA and SATA

Advanced Host Controller Interface (AHCI)

An efficient way for motherboards to work with SATA host bus adapters. Using AHCI unlocks some of the advanced features of SATA, such as hot-swapping and native command queuing (NCQ)

app store

Apple's mobile software storefront, where you can purchase apps for your smartphone, tablet, or other Apple products

Apple Pay

Apple's technology and sercie for making secure credit card payments in stores and apps via the iPhone and Apple Watch

Apps & Features

Area of the Windows 10 settings app that enables users to add and remove programs and windows features

AMD (Advanced Micro Devices)

CPU and chipset and manufacturer that competes with Intel. Produces FX, A-Series, Ryzen, and Opteron CPUs and APUs. Also produces video card processors under its ATI brand

Apple Filing Protocol (AFP)

Enables sharing between MACs. Also used by macOS Time Machine for backing up macOS over the network. Uses TCP port 548

ARM

Energy efficient processor design frequently used in mobile devices

AC (alternating current)

Type of electricity in which the flow of electrons alternates direction, back and forth, in a circuit

protective cover

A case or sleeve that protects a mobile device from physical damage.

single-sided RAM

Has chips on only one side as opposed to double-sided RAM.

ps

Linux command for listing all processes running on the computer.

iwconfig

Linux command for viewing and changing wireless settings.

pwd

Linux command that displays the user's current path.

grep

Linux command to search through text files or command outputs to find specific information or to filter out unneeded information.

chmod

Linux command used to change permissions.

retinal scanner

Biometric security device that authenticates an individual by comparing retinal scans. Rarer in the real world than in media such as movies or video games

Cat 5e

Category 5e wire; ANSI/TIA standard for UUTP wiring that can operate at up to 1 Gbps

Cat 6

Category 6 wire; ANSI/TIA standard for UTP wiring that can operate at up to 10 Gbps

chown

Linux command used to change the owner and the group to which a file or folder is associated.

fsck

Linux command-line tool that checks for hard drive errors

remnant

Potentially recoverable data on a hard drive that remains despite formatting or deleting

browser

Program specifically designed to retrieve, interpret, and display Web pages.

RSA token

Random-number generator used along with a user name and password to enhance security

punchdown tool

A specialized tool for connecting UTP wires to a punchdown block.

crimper

A specialized tool for connecting twisted pair wires to an RJ-45 connector. Also called a crimping tool.

positional audio

Range of commands for a sound card to place a sound anywhere in 3-D space.

transfer rate

Rate of data transferred between two devices, especially over the expansion bus.

structured cabling

ANSI/TIA standards that define methods of organizing the cables in a network for ease of repair and replacement

HTML (Hypertext Markup Language)

ASCII-based, script-like language for creating hypertext documents such as those on the World Wide Web.

Principle of Least Privilege

Accounts should have permission to access only the resources they need and no more.

LBA (logical block addressing)

Addressing scheme that presents storage chunks on a storage device to the OS as a sequence of blocks beginnign with LBA0. This saves the OS from having to deal directly with the details of how storage space is arranged on a hard drive or SSD.

Administrative shares

Administrator tool to give local admins access to hard drives and system root folders

USMT (User State Migration Tool)

Advanced application for file and settings transfer of many users. Only usable within a Windows Server Active Directory domain

Point-to-Point Tunneling Protocol (PPTP)

Advanced version of the Point-to-Point Protocol (PPP; used for dial-up Internet) that has improved VPN support

link light

An LED on NICs, hubs, and switches that lights up to show good connection between the devices.

activity light

An LED on a NIC, hub, or switch that blinks rapidly to show data transfers over the network

URL (Uniform Resource Locator)

An address that defines the location of a resource on the Internet. URLs are used most often in conjunction with HTML and the World Wide Web.

IMAP4 (Internet Message Access Protocol, version 4)

An alternative to POP3 that retrieves e-mail from an e-mail server; IMAP uses TCP port 143

QR scanner

An application or device capable of scanning and interpreting QR codes

BYOD (bring your own device)

An arrangement in some companies' IT departments where employees are permitted to use their own phones or other mobile devices instead of company-issued ones. Also, a feature of some wireless carriers where you can buy an unsubsidized device and use it to get cheaper wireless rates.

DDoS (Distributed Denial of Service)

An attack on a computer or network device in which multiple computers send data and requests to the device in an attempt to overwhelm it so that it cannot perform normal operations.

DoS (Denial of Service)

An attack on a computer resource that prevents it from performing its normal operations, usually by overwhelming it with large numbers of requests in an effort to monopolize its resources.

Cat 6a

Category 6a wire; augmented CAT 6 UTP wiring that supports 10-Gbps networks at the full 100-meter distance between a node and a switch.

End user agreement

Change management steps that entails educating and training users about what has changed and how to use any new systems, devices, or features

soft power

Characteristic of ATX motherboards, which can use software to turn the PC on and off. the physical manifestation of soft power is the power switch. Instead of the thick power cord used in AT systems, an ATX power switch is little more than a pair of small wires leading to the motherboard

rapid elasticity

Characteristic of cloud computing that enables cloud consumers to add or remove capacity quickly. Because cloud servers are powered by virtual machines, customers can start or shut down new instances of VMs or move the VMs to more powerful hardware

wildcard

Charcter- usually an asterisk (*) or question mark (?)- used during a search to represent search criteria. For instance, searching for *docx will return a list of all files with a .docx extension, regardless of the filename. The * is the wildcard in that search. Wildcards can be used in command-line commands to act on more than one file at a time

primary corona wire

Charges the photosensitive particles on the imaging drum. Replaced by the primary charge roller in newer laser printers

Super I/O chip

Chip specially designed to control low-speed, legacy devices such as the keyboard, mouse, and serial and parallel ports.

MCC (memory controller chip)

Chip that handles memory requests from the CPU. Although once a special chip, it has been integrated into the chipset or CPU on modern computers.

active PFC (power factor correction)

Circuitry built into PC power supplies to reduce harmonics

Hierarchical File System Plus (HFS+)

Classic file system used by older Macs. Still required for Time Machine drives. Replaced in new Macs and existing compatible systems with Apple File System (AFS)

BIOS (basic input/output services) (basic input/output system)

Classically, software routines burned on the system ROM of a PC. More commonly seen as firmware that directly controls a particular piece of hardware. This firmware handles startup operations and low-level control of hardware such as disk drives, the keyboard, and monitor.

change documentation

Collected documentation for all aspects of a change process, including plans leading up to the change as well as receipts, overtime documents, an inventory of changed systems, a list of created users, and signed end-user acceptance forms.

gain

Ratio of increase of radio frequency output provided by an antenna, measured in decibels (dB)

Aspect Ratio

Ratio of width to height of a display. Wide-screen displays such as modern TVs, desktop computer monitors, portable computer displays, and even smartphones commonly use 16:9 or 16:10, but you can find devices with many other aspect ratios.

plastic filament

Raw material that a typical 3-D printer melts and then extrudes to create physical pieces and parts

CD-ROM (compact disc read-only memory)

Read-only compact storage disc for audio or video data. CD-ROMs are read by using CD-ROM drives and optical drives with backward compatibility, such as DVD and Blu-ray Disc drives.

mirroring

Reading and writing data at the same time to two drives for fault tolerance purposes. Considered RAID level 1. Also called drive mirroring.

Incident report

Record of the details of an accident, including what happened and where it happened.

document findings, actions, and outcomes

Recording each troubleshooting job: what the problem was, how it was fixed, and other helpful information. (Step 6 of 6 in the CompTIA troubleshooting theory.)

dual boot

Refers to a computer with two operating systems installed, enabling users to choose which operating system to load on boot. Can also refer to kicking a device a second time just in case the first time didn't work.

client/server

Relationship in which client software obtains services from a server on behalf of a person.

remediation

Repairing damage caused by a virus.

UDF (universal data format)

Replaced the ISO-9660 formats, enabling any operating system and optical drive to read UDF formatted disks.

hot-swapping

Replacing a bad drive in a RAID array without needing to reboot or power down

Control Panel

Collection of Windows applets, or small programs, that can be used to configure various pieces of hardware and software in a system

profile (network)

Collection of information necessary to automatically connect to a network, stored by the network's SSID. Enables mobile and portable devices to easily use many networks

VoIP (Voice over Internet Protocol)

Collection of protocols that makes voice calls over a data network possible.

service pack

Collection of software patches released at one time by a software manufacturer

network

Collection of two or more computers interconnected by telephone lines, coaxial cables, satellite links, radio, and/or some other communication technique. Group of computers that are connected and that communicate with one another for a common purpose

group

Collection of user accounts that share the same access capabilities

sRGB

Color space standard that corresponds to Standard Dynamic Range (SDR)

Classless Inter-Domain Routing (CIDR)

Current system for creating and notating subnets, it replaced the older, less flexible three class system

1.5 Gbps

SATA drive variety with maximum throughput of 150 MBps See SATA

3 Gbps

SATA drive variety with maximum throughput of 300 MBps See SATA

SDRAM (synchronous DRAM)

DRAM that is synchronous, or tied to the system clock. This type of RAM is used in all modern systems.

DVD-ROM

DVD equivalent of the standard CD-ROM.

DVD-video

DVD format used exclusively to store digital video; capable of storing over two hours of high-quality video on a single DVD.

spear phishing

Dangerous targeted phishing attack on a group or individual that carefully uses details from the target's life to increase the odds they'll take the bait

resources

Data and services such as files, folders, drives, printers, connections, and so on

degaussing

Data destruction procedure used to reduce or remove the electromagnetic fields that store data on magnetic hard drives

SSD (solid state drive)

Data storage device that uses flash memory to store data.

NVMe (Non-Volatile Memory Express)

SSD technology that supports a communication connection between the operating system and the SSD directly through a PCIe bus lane, reducing latency and taking full advantage of the speeds of high-end SSDs. NVMe SSDs come in a few formats, such as an add-on expansion card, though most commonly in M.2 format. NVMe drives are a lot more expensive currently than other SSDs, but offer much higher speeds. NVMe drives use SATAe

g6 Gbps

Sata drive variety with maximum throughput of 600 MBps See SATA

program/programming

Series of binary electronic commands sent to a CPU to get work done.

OS (Operating System)

Series of programs and code that creates an interface so users can interact with a system's hardware; for example, Windows, Mac OS X, and Linux.

ATAPI (Advanced Technology Attachment Packet Interface)

Series of standards that enables mass storage deives other than hard drives to use the IDE/ATA controllers. Popular with optical drives. See also EIDE

bus

Series of wires connecting two or more separate electronic devices, enabling those devices to communicate. Also a network topology where computers all connect to a main line called a bus cable

print server

Server, computer, or standalone network device that shares access to a printer over a network

TCP/IP services

Services such as HTTP or SSH that run atop TCP/IP

encrypted

Data that has been passed through an encryption algorithm, rendering it unreadable without the decryption keys. see encryption

HDD (Hard Disk Drive)

Data-recording system using solid disks of magnetic material turning at high speeds to store and retrieve programs and data in a computer.

ad hoc mode

Decentralized wireless network mode, otherwise known as peer-to-peer mode, where each wireless node is in meshed contact with every other node

hardware token

Dedicated device that contains information used as an authentication factor when logging on to a secure site

bash

Default command shell on macOS and most Linux distributions. see shell

hardware protocol

Defines many aspects of a network, from the packet type to the cabling and connectors used.

AUP (Acceptable Use Policy)

Defines what actions employees may or may not perform on company equipment, including computers, phones, printers, and even the network itself. This policy defines the handling of passwords, e-mail, and many other issues.

scope of the change

Defines who and what the change will affect. May include an inventory of systems to change, people involved, time required, and estimated cost

Pixels per Inch (PPI)

Density of pixels on a display or a light sensor; the higher the density, the greater the resolution

TKIP (Temporal Key Integrity Protocol)

Deprecated encryption standard that provided a new encryption key for every sent packet.

x86

Describes 32-bit operating systems and software.

x64

Describes 64-bit operating systems and software.

pin 1

Designator used to ensure proper alignment of floppy drive and hard drive connectors.

router

Device connecting separate networks; forwards a packet from one network to another based on the network address for the protocol being used. For example, an IP router looks only at the IP network number. Routers operate at Layer 3 (Network) of the OSI seven-layer model

portable battery charger

Device containing a rechargeable battery that can be used to charge other devices, typically over USB, when no outlets are available

Digitizer(peripheral)

Device enabling users to paint, ink, pencil, or otherwise draw with a computer. Also known as a pen tablet.

projector

Device for projecting video images from PCs or other video sources, usually for audience presentations. Available in front- and rearview displays.

TDP (time-domain reflectometer)

Device for testing network cabling by measuring impedance (which is similar to resistance); any impedance means a bad cable

cable tester

Device for verifying that the connectors and wires in a cable (such as UTP) are in good order

POST card

Device installed into a motherboard expansion slot that assists in trouble- shooting boot problems by providing a two-digit code indicating the stop of the boot process where the problem is occurring.

memory

Device or medium for temporary storage of programs and data during program execution. Synonymous with storage, although it most frequently refers to the internal storage of a computer that can be directly addressed by operating instructions. A computer's temporary storage capacity is measured in kilobytes (KB), megabytes (MB), or gigabytes (GB) of RAM (random-access memory). Long-term data storage on hard drives and solid-state drives is also measured in megabytes, gigabytes, and terabytes

Credit card reader

Device that can be attached to mobile phones and tablets to take credit card payments

gyroscope

Device that can detect the position of the tablet or phone in 3-D space

camera

Device that captures visible light to preserve images in analog(film) or digital format. See digital camera

WAP (Wireless Access Point)

Device that centrally connects wireless network nodes.

security token

Devices that store some unique information that a user carries with them. May contain digital certificates, passwords, biometric data, or RSA tokens

wireless repeater/extender

Devices that receive and rebroadcast a Wi-Fi signal to increase coverage.

MFT (master file table)

Enhanced file allocation table used by NTFS. (See also FAT.)

PCI-X (PCI Extended)

Enhanced version of PCI, 64 bits wide. Typically seen in servers and high-end systems.

full device encryption

Enhances mobile device security by encrypting the device's internal storage

System on a Chip (SoC)

Single silicon die containing a CPU, GPU, ad other important support logic

Power conditioning

Ensuring and adjusting incoming AC wall power to as close to standard as possible. Most UPS devices provide power conditioning.

Mini-PCI

Specialized form of PCI designed for use in laptops.

Mini-PCIe

Specialized form of PCIe designed for use in laptops.

GPU (graphics processing unit)

Specialized processor that helps the CPU by taking over all of the 3-D rendering duties.

DNS domain

Specific branch of the DNS name space. First-level DNS domains include .com, .gov, and .edu.

DTS (Digital Theatre Systems)

Technology for sound reductions and channeling methods, similar to Dolby Digital.

Dolby digital

Technology for sound reductions and channeling methods used for digital audio.

cable Internet

Fast internet connection from a cable TV provider via RG-6 and RG-59 cable and a cable modem

SAS (serial-attached SCSI)

Fast, robust storage interface based on the SCSI command set. Also supports SATA drives. Used mainly in servers and storage arrays

emergency notification

Feature built into smartphones enabling them to receive messages from emergency broadcast systems, such as the Emergency Alert System (EAS) in the United States

DPI (dots per inch)

Measure of printer resolution that counts the dots the device can produce per linear (horizontal) inch.

swipe lock

Mobile device feature that uses a swipe gesture to unlock the mobile device.

application amanger

Mobile device interface for removing and managing apps running on the device.

cron

Tool used by many linux distributions for automatically running tasks based on a scheudule

change board

a group of representatives from around the organization who review and approve change proposals

MPEG-4

Moving Pictures Experts Group standard of video and audio compression offering improved compression over MPEG-2.

getting answers

eliciting answers

MPEG-2

Moving Pictures Experts Group standard of video and audio compression offering resolutions up to 1280 × 720 at 60 frames per second.

migration

Moving users from one operating system or hard drive to another

smartphone

A cell phone enhanced to do things formerly reserved for fully grown computers, such as Web browsing, document viewing, and media consumption

triple-channel architecture

A chipset feature similar to dual-channel RAM, but making use of three matched sticks of RAM instead of two

access control list (ACL)

A clearly defined list of permissions that specifies what actions an authenticated user may perform on a shared resource

Cellular card

A cellular modem on an expansion card designed for older laptop expansion slots. Current add-on cellular modems are typically attached via USB (and called USB modems by cellular service providers)

home server PC

A computer built to store files on a small office/home office (SOHO) network.

domain controller

A computer running Windows server that stores a set of domain accounts

Web server

A computer that stores and shares the files that make up Web sites.

Yagi

Multi-element antennas that increase signal gain in a specific direction. Resembles older television antennas, but smaller

prompt

A character or message provided by an operating system or program to indicate that it is ready to accept input.

microprocessor

"Brain" of a computer. Primary computer chip that determines relative speed and capabilities of the computer. Also called central processing unit CPU.

CPU (Central Processing Unit)

"Brain" of the computer. Microprocessor that handles primary calculations for the computer. CPUs are known by names such as Core i7 and Opteron

Mac

(Also Macintosh.) Common name for Apple Computers' flagship operating system; runs on Intel-based hardware. CompTIA refers to the operating system as Mac OS X. Apple calls the current operating system macOS

SATA power connector

15-pin, L-shaped connector used by SATA devices that support the hot-swappable feature.

Unicode

16-bit code that covers every character of the most common languages, plus several thousand symbols.

DIMM (dual inline memory module)

32- or 64-bit type of DRAM packaging with the distinction that each side of each tab inserted into the system performs a separate function. DIMMs come in a variety of sizes, with 184-, 240-, and 288-pin being the most common on desktop computers.

Standard Dynamic Range (SDR)

8-bit color standard that defines 256 colors or light intensities

VGA connector

A 15-pin, three-row, D-type VGA monitor connector. Goes by many other names, such as D-shell, D-subminiature connector, DB-15, DE15, and HD15. The oldest and least capable monitor connection type

multiple Desktops

A GUI feature that enables a computer to have more than one Desktop, each with its own icons and background. Mac OS X supports multiple Desktops with Spaces. Most Linux distros use multiple Desktops, often called workspaces. Microsoft introduced the feature with Windows 10.

swollen battery

A Li-Ion battery that has begun to swell as it fails, often due to manufacturing defects, heat, or overcharging. May also deform the device containing it. It is an explosion and fire risk if it ruptures, so dispose of it quickly and safely

exFAT

A Microsoft-proprietary file system that breaks the 4-GB file-size barrier, supporting files up to 16 exabytes (EB) and a theoretical partition limit of 64 zettabytes (ZB). Envisioned for use with flash media devices with a capacity exceeding 2 TB

RAID 0 + 1

A RAID 0 configuration created by combining two RAID 1's. Provide both speed and redundancy, but requires at least 4 disks

bootrec

A Windows Recovery Environment troubleshooting and repair tool that repairs the master boot record, boot sector, or BCD store. It replaces the fixboot and fixmbr Recovery Console commands used in Windows XP and earlier operating systems.

Windows XP mode

A Windows XP virtual machine that ships with Professional, Enterprise, and Ultimate editions of Windows 7 to enable users to run programs that don't work on Windows 7.

dock

A bar at the bottom of the Mac OS X desktop where application icons can be placed for easy access.

Advanced Encryption Standard (AES)

A block cipher created in the late 1990s that uses a 128-bit block size and a 128-, 192-, or 256-bit key size. Practically uncrackable.

stranded core

A cable that uses a bundle of tiny wire strands to transmit signals. Stranded core is not quite as good a conductor as solid core, but it will stand up to substantial handling without breaking.

solid core

A cable that uses a single solid wire (not hollow or stranded) to transmit signals.

CMOS battery

A coin cell lithium-ion battery that maintains power to the CMOS memory chip when the computer is otherwise unpowered. The usual battery size is CR2032

profile MDM

A collection of mobile device management (MDM) configuration and security settings that an administrator has created in order to apply those settings to particular categories of users or devices

hybrid cloud

A combination of cloud resources from more than one other cloud type, such as community, private, or public

xcopy

A command line tool used to copy multiple directories at once, which the copy command could not do

Terminal

A command-line tool available in macOS and various Linux distros

DISM (Deployment Image Servicing and Management)

A command-line tool bundled with Widnows 10 to support image deployment.. Also known as dism.exe

bcdedit

A command-line tool that enables you to view the BCD store, which lists the Windows boot options.

remote network installation

A common method of OS installation where the source files are placed in a shared directory on a network server. Then, whenever a tech needs to install a new OS, he or she can boot the computer, connect to the source location on the network, and start the installation from there

virtual machine (VM)

A complete environment for a guest operating system to function as though that operating system were installed on its own computer.

fully qualified domain name (FQDN)

A complete, bottom-to-top label of a DNS host going from the specific host to the top-level domain that holds it and all of the intervening domain layers, each layer being separated by a dot. FQDNs are entered into browser bars and other utilities in formats like mail.totalseminars.com

transfer belt

A component that enables color laser printers to transfer all color layers to the paper in a single pass (as opposed to a separate pass to print each color layer)

backlight

A component used in LCDs to illuminate an image. In older LCDs this was a CCFL; current LCDs use LEDs. See also CCFL, direct LED backlighting and edge LED backlighting

Audio Editing Workstation

A computer workstation for editing audio needs a fast multicore CPU, lots of RAM, and a large monitor. It also needs large, fast hard drives and a high-quality audio interface, and may make use of specialized input devices for mixing audio

video editing workstation

A computer workstation for editing video. Combine sthe hardware requirements of graphics and audio editing workstation. Typically makes use of two or more high-quality-calibrated monitors for both editing and viewing video at native resolution. The high-speed, high-capacity storage required to edit enormous video files is commonly provided by RAID arrays

Graphics Workstation

A computer workstation for graphics design that requires a fast, multicore CPU, maximum RAM, and serious storage space to work with massive graphics files. It also needs a high-quality graphics card and monitor

virtualization workstation

A computer workstation for simultaneous work in multiple virtual machines requires enough power for the host OS, plus any virtual machines, including their operating systems and software. In practice, this means powerful CPU's with many cores and maximum RAM

frame

A data unit transferred across a network. Frames consist of several parts, such as the sending and receiving MAC addresses, the data being sent, and the frame check sequence.

risk analysis

A detailed assessment of any problems that could result from a change

Network Attached Storage (NAS)

A device that attaches to a network for the sole purpose of storing and sharing files

bridge

A device that connects dissimilar network technologies that transmit the same signal

switch

A device that filters and forwards traffic based on some criteria. A bridge and a router are both examples of switches. In the command-line interface, a switch is a function that modifies the behavior of a command

CIFS (Common Internet File System)

A dialect of the Server message Block (SMB) protocol. Currently deprecated but still widely supported

installation media

A disc (typically a CD-ROM or DVD) or drive (as a USB flash drive) that holds all the necessary device drivers

chain of custody

A documented history of who has been in possession of a system.

signed driver

A driver designed specifically to work with Windows that has been tested and certified by Microsoft to work stably with Windows

catastrophic failure

A failure in which a component or whole system will not boot; usually related to a manufacturing defect of a component. Could also be caused by overheating and physical damage to computer components.

ITX

A family of motherboard form factors. Mini-ITX is the largest and the most popular of the ITX form factors but is still quite small.

SuperSpeed USB

A fast form of USB, with speeds up to 5 Gbps. Also called USB 3.0.

data roaming

A feature of cellular data systems that enables the signal to jump from cell tower to cell tower and from your provider to another provider without obvious notice.

Mission control

A feature of macOS that enables switching between open applications, windows, and more

Autorun

A feature that enables Windows to look for and read a file called autorun.inf immediately after a removable media device (optical drive or thumb drive) is inserted and automatically run whatever program the file lists

toner (printing)

A fine powder made up of plastic particles bonded to pigment particles, used to create the text and images on a page printed with a laser printer

subfolder

A folder located inside another folder

MDM (mobile device management)

A formalized structure that enables an organization to account for all the different types of devices used to process, store, transmit, and receive organizational data.

diskpart

A fully functioning command-line partitioning tool.

Personal Computer (PC)

A general computing device that runs Microsoft Windows and can be used for various tasks.

Trusted Platform Module (TPM)

A hardware platform for the acceleration of cryptographic functions and the secure storage of associated information. BitLocker, for example, requires a TPM chip on the motherboard to validate on boot that the computer has not changed

trusted root CA

A highly respected certificate authority (CA) that has been placed on the lists of trusted authorities built into Web browsers

HTPC

A home theater PC designed to attach to a TV or projector for movie and TV viewing

star bus topology

A hybrid network topology where the computers all connect to a central bus-a switch- and have a layout resembling a star

wireless mesh network (WMN)

A hybrid wireless topology in which most nodes connect in a mesh network while also including some wired machines. Nodes act like routers; they forward traffic for other nodes, but without wires

CMOS clear

A jumper setting or button on the motherboard that, when set, will revert CMOS settings to the factory defaults

self-grounding

A less than ideal method for ridding yourself of static electricity by touching a metal object such as a computer case. Alternatively, sending yourself to your own room as a form of punishment.

Single-factor authentication

A less-secure authentication process using only one of the authentication factors

drive letter

A letter designating a specific drive or partition.

DMZ (demilitarized zone)

A lightly protected or unprotected subnet network positioned between an outer firewall and an organization's highly protected internal network. DMZs are used mainly to host public address servers (such as Web servers).

profile (color)

A list of settings that a calibration device creates when calibrating monitors and printers

PRL (Preferred Roaming List)

A list that is occasionally and automatically updated to a phone's firmware by the carrier so that the phone will be configured with a particular carrier's networks and frequencies, in a priority order, that it should search for when it can't locate its home carrier network.

network topology diagram

A map of how everything in an organization's network (including switches, routers, WAPs, services, and workstations) connects. May indicate connection types, speed, technologies, and so on.

NAT (Network Address Translation)

A means of translating a system's IP address into another IP address before sending it out to a larger network. NAT manifests itself by a NAT program that runs on a system or a router. A network using NAT provides the systems on the network with private IP addresses. The system running the NAT software has two interfaces: one connected to the network and the other connected to the larger network. The NAT program takes packets from the client systems bound for the larger network and translates their internal private IP addresses to its own public IP address, enabling many systems to share a single IP address.

equipment rack

A metal structure used in equipment rooms to secure network hardware devices and patch panels. Most racks are 19" wide. Devices designed to fit in such a rack use a height measurement called units, or simply U.

network connection

A method for connecting two or more computers together.

liquid cooling

A method of cooling a PC that works by running some liquid— usually water—through a metal block that sits on top of the CPU, absorbing heat. The liquid gets heated by the block, runs out of the block and into something that cools the liquid, and is then pumped through the block again.

tablet

A mobile device consisting of a large touchscreen, enabling the user to browse the Web, view media, and even play games

Mobile hotspot

A mobile device that broadcasts a small Wi-Fi network to share its mobile data network connection with nearby Wi-Fi devices. Often these are standalone devices, though many cellular phones and data-connected tablets can be set up to act as hotspots.

Cloud computing

A model for enabling and accessing computing storage and other shared (or not shared ) resources on-demand. The "cloud" is based on servicing models that include IaaS, Paas, and SaaS, or hybrid mixtures of these services

ransomware

A nasty form of malware that encrypts data or drives on the infected system and demands payment, often within a limited timeframe, in exchange for the keys to decrypt the data

overloaded network

A network that, often due to a large public event, emergency, or network equipment failure, is unable to keep up with user demand. Users may have good signal quality but be unable to access data, text, or voice services

hybrid (networking)

A network topology that combines features from multiple other topologies, such as the star bus topology

broadcast

A network transmission addressed for every node on the network.

virtual switch

A non-physical version of a hardware switch, made by a hypervisor to network virtual machines

Startup Repair

A one-stop, do-it-all troubleshooting option that performs a number of boot repairs automatically.

patch panel

A panel containing a row of female connectors (ports) that terminate the horizontal cabling in the equipment room. Patch panels facilitate cabling organization and provide protection to horizontal cabling.

multi-rail

A power supply configuration where the current is split into multiple pathways, each with a maximum capacity and its own Over Current Protection (OCP) circuitry. CompTIA calls two-rail versions of this technology "dual rail."

gaming PC

A powerful desktop system designed to play the latest resource-hungry games using high-performance processors, RAM, and graphics cards. Typical peripherals are fast, high-quality monitors, rich sound systems, and input devices such as mice and keyboards tailored to high-performance gaming.

network technology

A practical application of a topology and other critical standards to provide a method to get data from one computer to another on a network. It defines many aspects of a network, from the topology, to the frame type, to the cabling and connectors used.

Inventory Management

A process for protecting devices and equipment by tagging them with barcodes or asset tags, and keeping track of these tagged devices

service

A process that runs in the background of a PC but displays no icons anywhere. You can view a list of services in the Windows Task Manager. Also, a program stored in a ROM chip

command

A request, typed from a terminal or embedded in a file, to perform an operation or to execute a particular program

network documentation

A road map to an organization's network configuration and topology for techs who need to change or repair the network

VESA mount

A screen or display bracket that follows the industry standard-established by the Video Electronics Standards Association (VESA)- which specifies size, location, and type of mounting points

proprietary crash screen

A screen, differing between operating systems, that indicates an NMI.

SNMP (Simple Network Management Protocol)

A set of standards for communication with devices connected to a TCP/IP network. Examples of these devices include routers, hubs, and switches. Uses port 161 and 162

MMC (Microsoft Management Console)

A shell program in Windows that holds individual utilities called snap-ins, designed for administration and troubleshooting. The MMC enables an administrator to customize management tools by picking and choosing from a list of snap-ins. Available snap-ins include Device Manager, Local Users and Groups, and Computer Management

workgroup

A simple, decentralized network that Windows PCs are configured to use by default.

run

A single piece of installed horizontal cabling.

Raid 5 volume (dynamic disks)

A software-based RAID 5 volume made up of three or more dynamic disks with equal-sized unallocated space. Created with Windows Disk Management

WinRE (Windows Recovery Environment)

A special set of tools in the Windows setup that enables you to access troubleshooting and repair features

hash

A special value computed from some other value using an irreversible computation. Has many uses in computing, and plays a key role in modern authentication systems. Instead of saving user passwords directly in a database (which would make them a huge target for attackers), well designed authentication systems computer and save only a (salted) hash of each password. When the user attempts to log in, the system hashes the provided password to see if it matches the saved hash. See also salted hash

Clock Wire (CLK)

A special wire that, when charged, tells the CPU that another piece of information is waiting to be processed

heat sink

A specially designed hunk of metal such as aluminum or cooper that conducts heat away from a CPU or other heat-producing component and out into fins that transfer the heat to circulating air. When used to cool a CPU, a heat sink is typically paired with a fan assembly to improve its performance

distribution (distro)

A specific variant of Linux.

Spinning Pinwheel of Death (SPoD)

A spinnign rainbow wheel that serves as the macOS indicator that an application isn't responding and may be busy or frozen

crossover cable

A standard UTP cable with one RJ-45 connector using the T568A standard and the other using T568B standard. This reserves the signal between sending and receiving wires and thus stimulates the connection to a switch.

Wi-Fi Protected Setup (WPS)

A standard included on many WAPs and clients to make secure connections easier to configure. WPS should be turned off, however, becuase it has a significant security flaw

PCI DSS (Payment Card Industry Data Security Standard)

A standard that sets common rules for systems that accept, process, transmit, or store credit/debit card payments. Often referred to as just PCI

DFS (Distributed File System)

A storage environment where shared files are accessed from storage devices within multiple servers, clients, and peer hosts.

convertible

A subset of 2-in-1 portables that use a hinge or latch mechanism to convert between laptop and tablet modes

thin client

A system designed to handle only very basic applications with an absolute minimum amount of hardware required by the operating system. Relies on resources from servers and thus needs a network connection. meets minimum requirements for selected OS.

Authentication factor

A thing that can be used to identify an individual, such as something they know (password), something they have (smart card), or something they are (fingerprint).

File Explorer

A tool in Windows 8/8.1/10 that enables users to browse files and folders. Previously known as Windows Explorer in Windows 7 and earlier versions

virtual desktop

A traditional desktop OS installed in a VM. A local system could run its own VM containing a virtual desktop, or just connect to a virtual desktop running on a remote server

automatic document feeder

A tray (usually on top) of a scanner or multi function device that holds a document and enables the device to grab and scan each page automatically for easier scanning, copying or faxing of long documents.

DB-9

A two-row DB connector (male) used to connect the computer's serial port to a serial-communication device such as a modem or a console port on a managed switch.

unattended installation

A type of OS installation where special scripts perform all the OS setup duties without human intervention.

gamepad

A type of game controller that usually consists of one or more thumbsticks, a directional pad, multiple face buttons, and two or more triggers

joystick

A type of game controller. Commonly used for flight-simulator games.

mirror set

A type of mirrored volume created with RAID 1. (See also mirroring.)

64-bit processing

A type of processing that can run a compatible 64-bit operating system, such as Windows 7, 8, 8.1, or 10, and 64-bit applications. 64-bit PCs have a 64-bit-wide address bus, enabling them to use more than 4 GB of RAM

IMSI (International Mobile Subscriber Identity)

A unique number that represents the actual user associated with a particular SIM card. The IMSI is usually available from the carrier, to ensure that stolen phones are not misused. The IMSI number can be used to unlock a phone as well.

profile (user)

A user profile describes a Windows user account's customized environment, including Desktop preferences, color schemes, shortcuts, and so on

virus

A virus is a program that has two jobs: to replicate and to activate. Replication means it copies itself. Activation is when a virus damages a system or data. A virsu can't self-replicate across networks; it needs human action to spread to other drives

smart watch

A watch incorporating features and communicating with a mobile device.

change management

A well defined process composed of many planning and execution steps that enables organizations to change their IT infrastructure in a safe, cost-effective manner

integer

A whole number. Integers and floating point numbers are handled differently in programs and by CPUs

WAN (Wide Area Network)

A widespread group of computers connected using long-distance technologies.

Credential manager

A windows Control panel applet which manages saved logon information for web sites, applications, and networks

HomeGroup

A windows feature that connects a group of computers using a common password- no special user names required. Each computer can be a member of only one homegroup at a time. Homegroups enable simple sharing of documents and printers between computers. Homegroups are available in Windows 7,8,8.1, and 10

AutoPlay

A windows feature that opens a dialog box when removable media is inserted into the computer, providing options based on what Windows finds on the drive, including starting the Autorun application

wait state

Occurs when the CPU has to wait for RAM to provide code. Also known as pipeline stall.

Accelerated processing unit (APU)

AMD product that consolidates the GPU and CPU into a single chip

Power Users group

After Administrator/Administrators, the second most powerful account and group type in Windows. Power users have differing capabilities in different versions of Windows.

Establish a plan of action to resolve the problem and implement the solution

After establishing and testing a theory about a particular problem, techs solve the problem (step 4 of 6 in the CompTIA troubleshooting methodology)

Establish a theory of probable cause (question the obvious)

After identifying a problem, techs question the obvious to determine what might be the source of the problem (step 2 of 6 in the CompTIA troubleshooting methodology)

EULA (End User License Agreement)

Agreement that accompanies a piece of software, to which the user must agree before using the software. Outlines the terms of use for the software and also lists any actions on the part of the user that violate the agreement.

protocol

Agreement that governs the procedures used to exchange information between cooperating entities. Usually includes how much information is to be sent, how often it is to be sent, how to recover from transmission errors, and who is to receive the information

instruction set

All of the machine-language commands that a particular CPU is designed to understand

option ROM

Alternative way of telling the system how to talk to a piece of hardware. Option ROM stores BIOS for the card in a chip on the card itself

imaging drum

Aluminium cylinder in a laser printer that is coated with particles of photosensitive compounds. When light hits these particles, whatever electrical charge they may have "drains" out through the grounded cylinder. After the particles are selectively charged by the laser, they attract the toner particles, forming the image that will be transferred. Often built into the toner cartridge. Also known as photosensitive drum

integrity

Always doing the right thing

latency

Amount of delay before a device may respond to a request; most commonly used in reference to RAM.

current

Amount of electrons moving past a certain point on a wire, measured in units called amperes. Also called amperage

Lightning

An 8-pin connector, proprietary to Apple, that can be inserted without regard to orientation. Used to connect mobile devices to a power or data source.

launcher

An Android app that serves as the device's desktop, often with more extensive customization features than launchers provided by Google or the device maker

SIMM (single inline memory module)

An early DRAM package format that came in two common sizes: 30-pin and 72-pin

computer

An electronic device that can perform calculations

microphone

An input device for recording audio.

game controller

An input device specifically designed for playing computer games. Typically has an array of buttons and triggers that control movement and actions on screen

Thunderbolt

An open standards connector interface that is primarily used to connect peripherals to devices, including mobile devices, if they have a corresponding port.

guest

An operating system running inside a virtual machine

line of sight

An unobstructed view between two devices. Required for IR communications.

comment

Annotation text included in scripts, programs, and configuration files, which may be used to describe what the code or setting does and how or why it does it. Most scripting, programming and configuration languages specify how to mark comment text.

RFI (radio frequency interference)

Another form of electrical interference caused by radio wave-emitting devices, such as cell phones, wireless network cards, and microwave ovens.

SATA 3.2

Another term for SATAe.

Reset to factory default

Another term for a factory reset

Personally Identifiable Information (PII)

Any data that can lead back to a specific individual

full-duplex

Any device that can send and receive data simultaneously.

peripheral

Any device that connects to the system unit

system fan

Any fan controlled by the motherboard but not directly attached to the CPU.

hot-swappable

Any hardware that may be attached to or removed from a PC without interrupting the PC's normal processing.

resistor

Any material or device that impedes the flow of electrons. Antistatic wrist straps and mats use tiny resistors to prevent a static discharge from racing through the device

FRU (field replaceable unit)

Any part of a PC that is considered to be replaceable "in the field," i.e., a customer location. There is no official list of FRUs—it is usually a matter of policy by the repair center.

removable media

Any storage on a computer that can be easily removed. For example, optical discs, flash drives, or memory cards.

unauthorized access

Anytime a person accesses resources in an unauthorized way. This access may or may not be malicious.

iCloud

Apple cloud-based storage. iCloud enables a user to back up all iPhone or iPad data, and makes that data accessible from anywhere. This includes any media purchased through iTunes and calendars, contacts, reminders, and so forth.

Boot camp

Apple tool used to install and boot to versions of Windows on a macOS computer

User Accounts applet

Applet in Control Panel that enables you to make changes to current accounts (local or global), and gives you access to the Settings charm (or app in Windows 10) when you opt to add a new account.

Computer management

Applet in Windows' Administrative Tools that contains several useful snap-ins, such as Device Manager and Disk Management.

disk quota

Application allowing network administrators to limit hard drive space usage.

Intrusion Prevention System (IPS)

Application similar to an intrusion detection system (IDS), except that it sits directly in the flow of network traffic. This enables it to stop ongoing attacks itself, but may slow down the network and be a single point of failure.

Intrusion Detection System (IDS)

Application that inspects packets, looking for active intrusions. Functions inside the network, looking for threats a firewall might miss, such as viruses, illegal logon attempts, and other well-known attacks. May also discover threats from inside the network, such as a vulnerability scanner run by a rogue employee

print spooler

Area of memory that queues up print jobs that the printer will handle sequentially.

telecommunications room

Area where all the cabling from individual computers in a network converges

queue

Area where objects wait their turn to be processed. Example: the print queue, where print jobs wait until it is their turn to be printed

LGA (Land Grid Array)

Arrangement of a large number of pins extending from the CPU socket to corresponding contact points on the bottom of the CPU

PGA (pin grid array)

Arrangement of a large number of pins extending from the bottom of the CPU package into corresponding holes in the CPU socket

zero-day attack

Attack targeting a previously unknown bug or vulnerability that software or hardware developers have had zero days to fix

man-in-the-middle (MITM)

Attacker serves as an intermediary between two systems, enabling the attacker to observe, redirect, or even alter messages passing in either direction.

Test the theory to determine cause

Attempt to reslove the issue by either confirming the theory and learning what needs to be done to fix the problem, or by not confirming the theory and forming a new one or escalating (Step 3 of 6 in the CompTIA troubleshooting methodology)

headphones

Audio output device that sits on top of or in a user's ears.

CD quality

Audio quality that has a sample rate of 44.4 KHz and a bit rate of 128 bits.

CAPTCHA (Completely Automated Public Turing Test to Tell Computers and Humans Apart)

Authentication challenge using images, videos, sounds, or other media to be identified by a user. Computers have a much more difficult time discerning the content of these tests than humans, making the challenge useful in determining if a human or a computer is attempting access

Kerberos

Authentication encryption developed by MIT to enable multiple brands of servers to authenticate multiple brands of clients.

two-factor authentication

Authentication process that provides additional secuirty by requiring two different authentication factors

MFA (Multifactor Authentication)

Authentication schema requiring more than one unique authentication factor. The factors are knowledge, possession, inherence, location, and temporal. For example, a password (knowledge factor) and a fingerprint (inherence factor) is a basic form of multifactor authentication

PKI (Public Key Infrastructure)

Authentication schema where public keys are exchanged between all parties using digital certificates, enabling secure communication over public networks.

Extensible Authentication Protocol (EAP)

Authentication wrapper that EAP-compliant applications can use to accept one of many types of authentication. While EAP is a general-purpose authentication wrapper, its only substantial use is in wireless networks.

DAC (Discretionary Access Control)

Authorization method based on the idea that there is an owner of a resource who may at his or her discretion assign access to that resource. DAC is considered much more flexible than mandatory access control (MAC).

MAC (Mandatory Access Control)

Authorization method in which the system grants access to resouces based on security labels and clearnace levels. Less flexible than discretionary access control (DAC), which lets users assign access levels to resources they own. MAC may be used in organizations with very high security needs.

image-level backup

Backing up a complete volume including any OS, boot files, applications, and data it contains

impersonation

Backing up a complete volume including any OS, boot files, applications, and data it contains

UPC (Universal Product Code)

Bar code used to track inventory

Hex (Hexadecimal)

Base-16 numbering system using ten digits (0 through 9) and six letters (A through F). In the computer world, shorthand way to write binary numbers by substituting one hex digit for a four-digit binary number (e.g., hex 9 = binary 1001).

packet

Basic component of communication over a network. Group of bits of fixed maximum size and well-defined format that is switched and transmitted as a single entity through a network. Contains source and destination address, data, and control information. Packets are included within (and are not the same thing as ) a frame

POST

Basic diagnostic routine completed by a system at the beginning of the boot process to make sure a display adapter and the system's memory are installed; it then searches for an operating system. If it finds one, it hands over control of the machine to the OS

Li-Ion (Lithium-Ion)

Battery commonly used in portable computing devices. Li-Ion batteries don't suffer from the memory effects of Nickel-Cadmium (Ni-Cd) batteries and provide much more power for a greater length of time.

Ni-CD (Nickel-Metal Hydride)

Battery used in early portable PCs. Ni-MH batteries had fewer issues with the memory effect than Ni-Cd batteries. Ni-MH batteries in computing devices have been replaced by Lithium-Ion batteries

pickup roller

Begins the printing process by grabbing paper to be printed and passing it over the separation pad

measured service

Billing model cloud service providers use to charge for services in small increments based on the computing resources the customer consumes

machine language

Binary instruction code that is understood by the CPU.

Steaming Media

Broadcast of data that is played on your computer and immediately discarded

tower spoofing

Broadcasting a rogue cellular signal that imitates a legitimate cell tower in order to trick cellular devices into connecting

malware

Broadly, software designed to use your computer or device against your wishes. Includes adware, spyware, viruses, ransomware, etc. may be part of seemingly legitimate software or installed by exploiting a vulnerability in the device

ISO-9660

CD format to support PC file systems on CD media. often referred to by the more generic term CD File System (CDFS)

CD-R (CD-recordable)

CD technology that accepts a single "burn" but cannot be erased after that one burn.

CD-RW (CD-rewritable)

CD technology that accepts multiple reads/writes like a hard drive.

music CD-R

CD using a special format for home recorders. Music CD-R makers pay a small royalty to avoid illegal music duplication.

ALU (arithmetic logic unit)

CPU logic circuits that perform basic arithmetic (add, subtract, multiply, and divide)

clock-multiplying CPU

CPU that takes the incoming clock signal and multiples it inside the CPU to let the internal circuitry of the CPU run faster.

dual-core

CPUs that have two execution units on the same physical chip but share caches and RAM.

STP (shielded twisted pair)

Cabling for networks, composed of pairs of wires twisted around each other at specific intervals. Twists serve to reduce interference (also called crosstalk)—the more twists, the less interference. Cable has metallic shielding to protect the wires from external interference.

coaxial cable

Cabling in which an internal conductor is surrounded by another, outer conductor, thus sharing the same axis

horizontal cabling

Cabling that connects the equipment room to the work areas.

digital camera

Camera that simulates film technology electronically.

sampling

Capturing sound waves in electronic format

Controller card

Card adapter that connects devices, such as a drive, to the main computer bus/motherboard

Product Release Instructions (PRI)

Carrier-made updates that modify many complex settings for CDMA devices to ready them deployment on the carrier's network

printhead

Case that holds the printwires in a dot-matrix printer.

external enclosure

Casing that encloses an external hard drive.

Cat 5

Category 5 wire; an ANSI/TIA standard for UTP wiring that can operate at up to 100 Mbps

Start button

Clickable element on the Windows taskbar that enables access to the Start menu

public cloud

Cloud network built and maintained by a large company for use by any individual or company who wants to create an account and start paying for services

private cloud

Cloud network built and maintained by or explicitly for a specific company or organization. Often on-site, but may be provided by a third party. While a public cloud network often requires more expertise and costs more, especially up front, it also enables greater customization and security

Community cloud

Cloud network that serves a community or group with shared needs and interests, such as hospitals or defense contractors

SaaS (Software as a Service)

Cloud-based service to store, distribute, and update programs and applications. The SaaS model provides access to necessary application wherever you have an Internet connection, often without having to carry data with your regularly update software.At the enterprise level, the subscription model of many SaaS providers makes it easier to budget and keep hundreds or thousands of computers up to date.

virtual application streaming

Cloud-based versions of local application. Virtual application streaming enables access to programs using almost any device that can browse the Internet

PaaS (Platform as a Service)

Cloud-based virtual server(s). These virtualized platforms give programmers tools needed to deploy, administer, and maintain a Web application.

IaaS (Infrastructure as a Service)

Cloud-hosted provider of virtualized servers and networks.

RG-59

Coaxial cable used for cable television, cable modems, and broadcast TV; thinner than RG-6, which makes it suitable for shorter patch cables

RG-6

Coaxial cabling used for cable television. It has a 75-ohm impedance and uses an F-type connector

signature (malware)

Code pattern of a known virus or malware that antivirus/anti-malware software uses to detect malware

Digital Rights Management (DRM)

Code schemes for enforcing what users can and can't do with commercial software or digital media files

product key

Code used during installation to verify legitimacy of the software.

Plug and Play (PnP)

Combination of smart PCs, smart devices, and smart operating systems that automatically configure all necessary system resources and ports when you install a new peripheral device.

CFS (Command File System)

Command file system or common file system

reg

Command line tool for editing the Registry

copy command

Command line tool used to make a copy of a file and paste it in another location

pipe

Command-line operator that uses the | symbol to "pipe" output from one command to another, instead of printing it to the screen

nslookup

Command-line program in Windows used to determine exactly what information the DNS server is providing about a specific host name.

netstat

Command-line tool in Windows and Linux to identify inbound and outbound TCP/IP connections with the host

Windows PowerShell

Command-line tool included with Windows. Offers a number of powerful scripting tools for automating changes both on local machines and over networks.

ipconfig

Command-line utility for Windows servers and workstations that displays the current TCP/IP configuration of the machine. Similar to ifconfig

sfc (System File Checker)

Command-prompt program (sfc.exe) that scans, detects, and restores Windows system files, folders, and paths.

F-type connector

Common coax connector secured with a screw connector

serial port

Common connector on older PC. Connects input devices (such as a mouse) or communications devices (such as a modem). Also referred to as a COM port.

Wi-Fi (Wireless Fidelity)

Common name for the IEEE 802.11 wireless Ethernet standard.

Broadband

Commonly understood as a reference to high-speed, always-on communication links that can move large files much more quickly than a regular phone line.

TCP/IP (Transmission Control Protocol/Internet Protocol)

Communication protocols developed by the US Department of Defense to enable dissimilar computers to share information over a network. TCP/IP is the primary protocol of most modern networks, including the internet

eliciting answers

Communication strategy designed to help techs understand a user's problems better. Works by listening to a user's description of a problem and then asking cogent questions.

www.comptia.org

CompTIA's Web site.

thick client

CompTIAs name for a standard desktop build. Runs a modern operating system and general productivity applications to accomplish the vast majority of tasks needed by office and home users. It does not need a network connection to run and it meets the recommended requirements for its OS

Pearson VUE

Company that administers the CompTIA A+ exams.

ISP (Internet Service Provider)

Company that provides access to the Internet, usually for money

ISO file

Complete copy (or image) of a storage media device, typically used for optical discs. ISO image files typically have a file extension of .iso.

Zigbee

Completely open wireless networking protocol designed to address home automation challenges

Registry

Complex binary file used to store configuration data about a particular Windows system. To edit the Registry, users can use the applets found in the Control Panel or regedit.exe or regedt32.exe.

RIP (Raster Image Processor)

Component in a printer that translates the raster image into commands for the printer.

erase lamp

Component inside laser printers that uses light to make the coating of the photosensitive drum conductive.

GDI (graphical device interface)

Component of Windows that utilizes the CPU rather than the printer to process a print job as a bitmapped image of each page.

rainbow table

Compressed file that contains a mapping of hashed passwords (or other account information) to the corresponding unhashed, plaintext password. Rainbow tables are useful for reversing unsalted hashes in older/legacy authentication systems, but are useless for reversing properly salted hashes used by well-designed, modern authentication systems

file server

Computer designated to store software, courseware, administrative tools, and other data on a LAN or WAN. It "serves" this information to other computers via the network when users enter their personal access codes.

AnandTech.com

Computer hardware, technology, and Internet news and information site

zombie

Computer infected with malware that has turned it into a botnet member

video capture

Computer jargon for the recording of video information, such as TV shows or movies.

molex connector

Computer power connector used by optical drives, hard drives, and case fans. Keyed to prevent it from being inserted into a power port improperly.

Client

Computer program that uses the services of another computer program. Also software that extracts information from a server; your auto-dial phone is a client and the phone company is its server. Also, a machine that accesses shared resources on a server

server

Computer that shares its resources, such as printers and files, with other computers on a network. Example: network file system server that shares its disk space with a workstation that does not have a disk drive of its own

VR (Virtual Reality)

Computer-generated 3-D video and audio paired with special hardware (usually including a VR headset and sensors to detect movement) to create an immersive simulation a user navigates by moving around in physical space

compliance

Concept that members of an organization must abide by the rules created by and applying to that organization (including government regularions). For a technician, this often defines what software can or cannot be installed on an organiztion's computers

parallel port

Connection for the synchronous, high-speed flow of data along parallel lines to a device, usually a printer.

Transmission Control Protocol (TCP)

Connection-oriented protocol used with TCP/IP

PCIe 6/8-pin connector

Connector on some power supplies for powering a dedicated graphics card

expansion slots

Connectors on a motherboard that enable users to add optional components to a system. (See also AGP, PCI, and PCIe.)

HBA (host bus adapter)

Connects SATA devices to the expansion bus. Also known as the SATA controller.

IEC-320

Connects the cable supplying AC power from a wall outlet into the power supply.

resource pooling

Consolidating resources from many systems into a smaller number of more powerful systems, reducing power, maintenance, and hardware costs.

PCMCIA (Personal Computer Memory Card International Association)

Consortium of computer manufacturers who devised the PC card standard for credit card-sized adapter cards that add functionality in older notebook computers and other computer devices. PCMCIA shut down in 2009

user account

Container that identifies a user to an application, operating system, or network, including name, password, user name, groups to which the user belongs, and other information based on the user and the OS being used. Usually defines the rights and roles a user plays on a system.

notification area

Contains icons representing background processes, the system clock, and volume control. Located by default at the right edge of the Windows taskbar. Most users call this area the system tray.

system tray

Contains icons representing background processes and the system clock. Located by default at the right edge of the Windows taskbar. Accurately called the notification area.

Taskbar

Contains the Start button, Search box (windows 10), pinned apps, running apps, and the notification are. Located by default at the bottom of the desktop

loop

Control construct used in a script or program to repeat a sequence of instructions when certain conditions are met. For example, a script could use a loop to a set of instructions for resizing an image once for every image file in a directory.

File History

Control panel applet introduced in Window 8 for backing up personal files and folders

policies

Control permission to perform a given action, such as accessing a command prompt, installing software or logging on at a certain time of day. Contrast with true permissions, which control access to specific resources

expansion bus crystal

Controls the speed of the expansion bus.

printed circuit board (PCB)

Copper etched onto a nonconductive material and then coated with some sort of epoxy for strength.

kernel

Core portion of program that resides in memory and performs the most essential operating system tasks.

thin provisioning

Creating a Storage Space that reports a size greater than the actual capacity installed in the computer, with the ability to later add more physical capacity up to the reported size

tunneling

Creating an encrypted link between two programs on two separate computers.

user password

Credentials assigned to a login account that does not have administrative capabilities

administrator password

Credentials for the system administrator account

burn-in failure

Critical failure usually associated with manufacturing defects.

system crystal

Crystal that provides the speed signals for the CPU and the rest of the system.

DB connectors

D-shaped connectors used for a variety of connections in the PC and networking world. Can be male (with prongs) or female (with holes) and have a varying number of pins or sockets. Also called D-sub, D-subminiature, or D-shell connectors. They are still reasonably common, but rarely used

open source

Describes a product fo which the plans, schematics, recipes, or other information used to create it are released by its creator or distributor. Most commonly applied to software

closed source

Describes a product for which the plans, schematics, recipes, or other information used to create it are solely controlled by its creator or distributor. Most commonly applied to software

UNC (Universal Naming Convention)

Describes any shared resource in a network using the convention \\<server name>\<name of shared resource>.

Registration(printing)

Describes how accurately the printer lays down each color layer that makes up a page or image. Poor registration can result in muddled colors or a fringe of pure color around a shape or image. Printers usually have a routine (which may mention calibration, alignment, or registration) for detecting and fixing alignment issues

monaural

Describes recording tracks from one source (microphone) as opposed to stereo, which uses two sources.

stereo

Describes recording tracks from two sources (microphones) as opposed to monaural, which uses one source.

nonvolatile

Describes storage that retains data even if power is removed; typically refers to a ROM or flash ROM chip, but also could be applied to hard drives, optical media, and other storage devices

polarization

Describes the alignement (such as vertical or horizontal) of antennas and the signals they transmit. Because polarization, a Wi-FI client and WAP will have the best connection when their antennas are oriented

permission propagation

Describes what happens to permissions on an object, such as a file or folder, when you move or copy it

screen orientation

Describes whether a mobile device screen is in portrait or landscape mode, and the device settings that govern when the orientation may change. When the screen orientation setting is in automatic mode, the user interface (UI) will switch between portrait and landscape modes based on the device's orientation in physical space.

PCI (Peripheral Component Interconnect)

Design architecture for the expansion bus on the computer motherboard that enabled system components to be added to the computer. Used parallel communication. Local bus standard, meaning that devices added to a computer through this port used the processor at the motherboard's full speed (up to 33 MHz) rather than at the slower 8-MHz speed of the regular bus. Moved data 32 or 64 bits at a time rather than the 8 or 16 bits the older ISA buses supported

ISA (Industry Standard Architecture)

Design found in the original IBM PC for the slots that allowed additional hardware to be connected to the computer's motherboard. An 8-bit, 8.33-MHz expansion bus was designed by IBM for its AT computer and released to the public domain. An improved 16-bit bus was also released to the public domain. Replaced by PCI in the mid-1990s.

NLQ (near-letter quality)

Designation for dot-matrix printers that use 24-pin printheads.

modem (modulate/demodulate)

Device that converts a digital bit stream into an analog signal (modulation) and converts incoming analog signals back into digital signals (demodulation). An analog communications channel is typically a telephone line, and analog signals are typically sounds

3-D printer

Device that creates (or "prints") three-dimensional objects, typically by melting material (such as plastic filament) reassembling it in layers

USB hub

Device that extends a single USB connection to two or more USB ports, almost always directly from one of the USB ports connected to the root hub.

VoIP phone

Device that looks like a regular landline phone but uses VoIP to communicate over a computer network

speaker

Device that outputs sound by using magnetically driven diaphragm

port replicator

Device that plugs into a USB port or other specialized port and offers common PC ports, such as serial, parallel, USB, network, and PS/2. By plugging your note- book computer into the port replicator, you can instantly connect the computer to non-portable components such as a printer, scanner, monitor, or full-sized keyboard. Port replica- tors are typically used at home or in the office with the non- portable equipment already connected.

docking station

Device that provides a portable computer extra features such as a DVD drive or PC Card, in addition to legacy and modern ports. Similar to a port replicator. Also, a charging station for mobile devices

firewall

Device that restricts traffic between a local network and the Internet.

smart card reader

Device that scans the smart card chip, such as those in ID badges. Common applications include enhancing the security of doors or laptops

UPS (uninterruptible power supply)

Device that supplies continuous clean power to a computer system the whole time the computer is on. Protects against power outages and sags. (and corresponding data loss)

analog

Device that uses a physical quantity, such as length or voltage, to represent the value of a number. By contrast, digital storage relies on a coding system of numeric units

loopback plug

Device used during loopback tests to check the female connector on a NIC.

inverter

Device used to convert DC current into AC. Commonly used with CCFLs in laptops and flatbed scanners.

multimeter

Device used to measure voltage, amperage, and resistance.

card reader

Device with which you can read data from one of several types of flash memory.

real-time clock (RTC)

Device within the CMOS memory chip that provides date and time information to the computer and operating system

fitness monitor

Devices that encourage physical fitness by counting steps using accelerometers, registering heart rate through sensors, using GPS to track exercise, and offering vibration tools to remind the user to get moving. Fitness trackers fit into one of two type: fobs that clip to the body and more sophisticated fitness bands or watches.

driver signing

Digital signature for drivers used by Windows to protect against potentially bad drivers.

DisplayPort

Digital video connector used by Apple Mac desktop models and some PCs, notably from Dell. Designed by VESA as a royalty-free connector to replace VGA and DVI.

root directory

Directory that contains all other directories.

RAID 6

Disk striping with extra parity. Like RAID 5, but with more parity data. Requires five or more drives, but you can lose up to two drives at once and your data is still protected.

Native Command Queuing (NCQ)

Disk-optimization feature for SATA drives enabling faster read and write speeds

fdisk

Disk-partitioning utility used in DOS and Windows 9x systems.

DLP (digital light processing)

Display technology that reflects and directs light onto a display surface using micromechanically operated mirrors.

IPS (in-plane switching)

Display technology that replaces the older twisted nematic (TN) panels for more accurate colors and a wider viewing angle.

vertical alignment (VA)

Display technology used in mid-range LCD panels. VA refers to how the liquid crystal matrix is arranged within the panel

OLED (organic light-emitting diode)

Display technology where an organic compound provides the light for the screen, thus eliminating the need for a backlight or inverter. Used in high-end TVs and small devices such as smart watches, smartphones, and VR headsets

rearview projector

Display using a projector that illuminates a semi-transparent screen from the back. Once popular for televisions, but virtually unheard of for PCs

Ethic of Reciprocity (Golden Rule)

Do unto others as you would have them do unto you

entry control roster

Document for recording who enters and leaves a building

BitLocker Drive Encryption

Drive encryption software offered in high-end versions of Windows. BitLocker requires a special chip to validate hardware status and to ensure that the computer hasn't been hacked.

mount point

Drive that functions like a folder mounted into another drive.

optical drive

Drive used to read/write to optical discs, such as CDs or DVDs.

unsigned driver

Driver that has not gone through the Windows Certification Program to ensure compatibility. Rarely seen on modern Windows machines, as only the last of the 32-bit Windows versions support unsigned drivers

terminal

Dumb device connected to a mainframe or computer network that acts as a point for entry or retrieval of information

parity RAM

Earliest form of error-detecting RAM; stored an extra bit (called the parity bit) to verify the data.

parity

Early method of error detection where a small group of bits being transferred is compared to a single parity bit set to make the total bits odd or even. The receiving device reads the parity bit and determines if the data is valid, based on the oddness or evenness of the parity bit

electromagnetic interference (EMI)

Electrical interference from one device to another, resulting in poor performance of the device being interfered with. Examples: Static on your TV while running a blow dryer, or placing two monitors too close together and getting a "shaky" screen.

laser printer

Electro-photographic printer in which a laser is used as the light source.

chipset

Electronic chips, specially designed to work together, that handle all of the low-level functions of a PC. In the original PC, the chipset consisted of close to 30 different chips. For most of the 90's and 00's, chipsets consisted of one, two, or three seperate chips embedded into a motherboard. Today, CPUs have controllers built in, such as the memory and display controllers. Almost all chipsets are now a single chip

hub

Electronic device that sits at the center of a star topology network, providing a common point for the connection of network devices. Hubs repeat all information out to all ports and have been replaced by switches, although the term "hub" is still commonly used.

ohm (s)

Electronic measurement of a cable's impedance

partitioning

Electronically subdividing a physical hard drive into groups called partitions (or volumes).

firmware

Embedded programs or code stored on a ROM chip. Generally OS-independent, thus allowing devices to operate in a wide variety of circumstances without direct OS support. The system BIOS is firmware.

PPP (Point-to-Point Protocol)

Enables a computer to connect to the Internet through a dial-in connection and enjoy most of the benefits of a direct connection.

VPN (Virtual Private Network)

Encrypted connection over the Internet between a computer or remote network and a private network.

Transport Layer Security (TLS)

Encryption protocol used to securely connect between servers and clients, such as when your Web browser securely connects to Amazon's servers to make a purchase. Replaces SSL

system/application log errors

Errors and warnings in the system/application logs may indicate the presence of a malware infestation and the scope of its effects.

10BasetT

Ethernet cabling system designed to run at 10 Mbps on twister pair cabling

100BaseT

Ethernet cabling system designed to run at 100 Mbps on twister pair cabling. Also called Fast Ethernet

1000BaseT

Ethernet cabling system designed to run at 1000 Mbps on twister pair cabling. Also called Gigabit Ethernet

10 Gigabit Ethernet

Ethernet standard that supports transfer rates up to 10 Gbps and is common on server-to-server connections. Requires Cat 6 or better twisted pair or fiber optic cabling

General Data Protection Regulation (GDPR)

European Union law that defines a broad set of rights and protections of personal information for citizens of the EU

msconfig (System Configuration utility)

Executable file that runs the Windows System Configuration utility, which enables users to configure a system's boot files and critical system files. Often used for the name of the utility, as in "just run msconfig." This functionality moved to Task Manager in Windows 8

NIC (Network Interface Card or Controller)

Expansion card or motherboard interface that enables a PC to connect to a network via a network cable. A wireless NIC enables connection via radio waves rather than a physical cable.

sound card

Expansion card that can produce audible tones when connected to a set of speakers.

Video card

Expansion card that works with the CPU to produce the images displayed on your computer's display.

MIDI-enabled device

External device that enables you to input digital sound information in the MIDI format; for example, a MIDI keyboard (the piano kind).

password reset disc

External storage media such as an optical disc or USB flash drive which users can recover a lost password without losing access to any encrypted, or password-protected, data. The password reset disc must be created proactively; if a user loses a password and did not already make a reset disc, it will be of no help to create one after the loss

HTTP (Hypertext Transfer Protocol)

Extremely fast protocol used for network file transfers on the World Wide Web. Uses port 80

Library

Feature in Windows 7 and later that aggregates folders from multiple locations and places them in a single, easy-to-find spot in Windows Explorer or File Explorer. Default libraries in Windows include Documents, Music, Pictures, and Videos.

geotracking

Feature in cellular phones that enables the cell phone companies and government agencies to use the ID or MAC address to pinpoint where your phone is at any given time.

accelerometer

Feature in smartphones and tablets that rotates the screen when the device is physically rotated

side-by-side apps

Feature introduced in Windows 8 for quickly pinning an app to the left or right half of a screen

MIMO (multiple input-multiple output)

Feature of 802.11n devices that enables the simultaneous connection of up to four antennas, greatly increasing throughput. 802.11ac also uses MU-MIMO which gives a WAP the capability to broadcast to multiple users simultaneously

object access auditing

Feature of Event Viewer's Security section that creates an entry in the Security Log when certain objects are accessed, such as a file or folder.

event auditing

Feature of Event Viewer's Security section that creates an entry in the Security Log when certain events happen, such as a user logging on.

APIPA (Automatic Private IP addressing)

Feature of Windows that automatically assigns an IP address to the system when the client cannot obtain an IP address automatically

Remote Assistance

Feature of Windows that enables users to give anyone control of his or her desktop over the Internet.

Compatability Modes

Feature of Windows to enable software written for previous versions of Windows to operate in newer operating systems

chassis intrusion detection

Feature offered in some chassis that trips a switch when the chassis is opened.

auto-brightness

Feature on modern mobile devices that attempts to use a camera or other light sensor to adjust screen brightness based on how light or dark it is.

quad-channel architecture

Feature similar to dual-channel RAM, but requiring four sticks instead of two.

metered service

Fee charged by cloud service providers on the basis of how much a resource was used. Fees may be based on things like access time, bandwidth used, bytes uploaded or downloaded, CPU usage, and other resource usage metrics

Information Technology (IT)

Field of computers, their operation and their maintenance

GDDR5

Fifth generation of graphical DDR RAM found on high-performance video cards

Boot Configuration Data (BCD) file

File that contains information about the various operating systems installed on the system as well as instructions for how to actually load (bootstrap) them.

Security tab

File/folder administrative preferences found in the Properties dialog in both File Explorer and Windows Explorer. These preferences govern user and group access to a particular file or folder

log files

Files created in Windows to track the progress of certain processes.

definition file

Files that enable anti-malware programs to identify viruses on your system and clean them. These files should be updated often. Also called signature files

IEEE 1394a

FireWire standard that runs at 400 Mbps.

IEEE 1394b

FireWire standard that runs at 800 Mbps.

software firewall

Firewall implemented in software running on servers or workstations

hardware firewall

Firewall implemented within networking hardware such as a router. See firewall

Level 1 (L1) cache

First RAM cache accessed by the CPU, which stores only the absolute most-accessed programming and data used by currently running threads. Always the smallest and fastest cache on the CPU.

DOS (Disk Operating System)

First popular operating system available for PCs. A text-based, single-tasking operating system that was not completely replaced until the introduction of Windows 95.

logon screen

First screen of the Windows interface, used to log on to the computer system.

boot sector

First sector on a storage drive. The boot-up software in ROM tells the computer to load whatever program is found there. If a system disk is read, the program in the boot record directs the computer to the root directory to load the operating system

root keys

Five main categories in the Windows Registry: HKEY_CLASSES_ROOT HKEY_CURRENT_USER HKEY_USERS HKEY_LOCAL_MACHINE HKEY_CURRENT_CONFIG

spindle speed

Fixed speed in revolutons per minute (RPM) at which a given HDD's platters spin. The most common speeds are 5400 and 7200 RPM; higher performance drives (far less common) run at 10,000 and 15,000 ROM. also called rotational speed

system ROM

Flash ROM chip that stores the system BIOS

USB thumb drive

Flash memory device that uses the standard USB connection.

motherboard

Flat piece of circuit board that resides inside your computer case and has a number of connectors on it. Every device in a PC connects directly or indirectly to the motherboard, including CPU, RAM, hard drives, optical drives, keyboard, mouse, and video cards.

touchpad

Flat, touch-sensitive pad that serves as a pointing device for most laptops.

Public folder

Folder that all users can access and share with all other users on the system or network.

extra battery pack

For devices with removable batteries, an extra battery that can be swapped in as needed

hard reset

For mobile devices, another term for a factory reset. Don't confuse this with a hard reboot. See factory reset

digital certificate

Form in which a public key is sent from a Web server to a Web browser so that the browser can decrypt the data sent by the server.

dual-channel memory

Form of DDR, DDR2, and DDR3 memory access used by many motherboards that requires two identical sticks of DDR, DDR2, or DDR3 RAM.

tailgating

Form of infiltration and social engineering that involves following someone else through a door as if you belong in the building

FPU (floating point unit)

Formal term for math coprocessor (also called a numeric processor) circuitry inside a CPU. A math coprocessor calculates by using a floating point numerical system (which allows for decimals). Before the Intel 80486, FPUs were separate chips from the CPU.

full format

Format process that tests every sector to mark out the unusable ones in the file allocation table (FAT). see formatting

high-level formatting

Format that sets up a file system on a drive.

Computing process

Four parts of a computer's operation: input, processing, output, and storage.

Long Term Evolution (LTE)

Fourth-generation cellular network technology supporting theoretical download speeds up to 1 Gbps and upload speeds up to 100 Mbps. Marketed as and now now generally accepted as a true 4G technology

rogue anti-malware

Free applications that claim to be anti-malware, but which are actually themselves malware

ADSL (asymmetric digital subscriber line)

Fully digital, dedicated connection to the telephone system that provides average download speeds of 3-15Mbps and upload speeds of 384 Kbps to 15 Mbps. Asymmetric identifies that upload and download speeds are different with download usually being significantly faster than upload.

conditionals

Functions that enable a script or program to perform different actions under different conditions. For example, a backup script might "run" every hour, but only create a new backup if the system is idel and if it has been at least a day since the last backup was created

System monitor

GNOME 3 utility that can evaluate and monitor system resources, such as CPU usage and memory usage

integrated GPU

GPU integrated with the motherboard or processor, in contrast to GPUs on separate graphics cards. This typically lowers power consumption, saves space, reduces heat, and may speed up communication with the GPU

dynamic range

Gamut of color or intensity of light that can be displayed or detected by a device

content filtering

Gating access to insecure or objectionable sites using certificates or parental control tools

I/O (input/output)

General term for reading and writing data to a computer. "Input" includes data entered from a keyboard, identified by a pointing device (such as a mouse), or loaded from a disk. "Output" includes writing information to a disk, viewing it on a monitor, or printing it to a printer.

USB (Universal Serial Bus)

General-purpose serial interconnect for keyboards, printers, joysticks, and many other devices. Enables hot-swapping of devices.

CDFS (Compact Disc File System)

Generic name for ISO-9660. File structure, rules, and conventions used when organizing and storing files and data on a CD

stick

Generic name for a single physical SIMM, RIMM, or DIMM.

applet

Generic term for a program in the Windows Control Panel

boot sequence

List containing information telling the bootstrap loader in which order to check the available storage devices for an OS. Configurable in CMOS setup.

ROM (Read Only Memory)

Generic term for nonvolatile memory that can be read from but not written to. This means that code and data stored in ROM cannot be corrupted by accidental erasure. Additionally, ROM retains its data when power is removed, which makes it the perfect medium for storing BIOS data or information such as scientific constants.

toner (networking)

Generic term for two devices used together - a tone generator and a tone probe (locator)- to trace cables by sending an electrical signal along a wire at a particular frequency. The tone probe then emits a sound when it distinguishes that frequency

vendor specific

Generically, a proprietary product or technology that doesn't use common, open standards, Vendor-specific products or features may not be completely or even partially compatible with products from other vendors. Also applies to stores that only sell products from one manufacturer, like the Apple store

Key fob

Generically, just about anything attached to a key ring that isn't a key. Some security tools, such as hardware security tokens and RFID authentication devices, are commonly designed as key fobs

remote desktop

Generically, the process of using one system to access the desktop or graphical user interface (GUI) of a remote system

swipe

Gesture for mobile devices where you hold your finger on the screen and slide it across the screen, either right to left or top to bottom, depending on the type of application.

Chrome OS

Google's Linux-based operating system designed to connect users via the Internet into google applications, such as Gmail, Google Docs, and more. Chrome OS comes preinstalled on purpose-built hardware such as the Chromebook portable computers

Google Play

Google's app and media store for Android devices

printwires

Grid of tiny pins in a dot-matrix printer that strike an inked printer ribbon to produce images on paper.

Administrative Tools

Group of Control Panel applets, including computer management, Event Viewer, Performance Monitor, and Task Scheduler

LAN (Local Area Network)

Group of computers connected via cabling, radio, or infrared that use this connectivity to share resources such as printers and mass storage.

Domain

Groupings of users, computers or networks. In Microsoft networking, a domain is a group of computers and users that share a common account database and common security policy. On the Internet, a domain is a group a common security policy. On the Internet, a domain is a group of computers that share a common element in their hierarchical name. Other types of domains exist- e.g. broadcast domain etc.

hard drive

HDD

display adapter

Handles all the communication between the CPU and the monitor. Also known as a video card.

Personalization Settings

Handles user preferences such as the background picture for both the desktop and lock screen, colors of interface elements, themes, which elements show on the Start screen, and so on. Replaced the Personalization applet in Windows 10

chkdsk (CheckDisk)

Hard drive error detection and, to a certain extent, correction utility in Windows, launched from the command-line interface. Originally a DOS command (chkdsk.exe); also the executable for the graphical Error-checking tool.

basic disk

Hard drive partitioned in the "classic" way with a master boot record (MBR) and partition table. see also dynamic disks.

disk thrashing

Hard drive that is constantly being accessed due to lack of available system memory. When system memory runs low, a Windows system will utilize hard disk space as "virtual" memory, thus causing an unusual amount of hard drive access.

mass storage

Hard drives, optical discs, removable media drives, etc.

smart card

Hardware authentication involving a credit card-sized card with circuitry that can be used to identify the bearer of that card.

plug

Hardware connection with some sort of projection that connects to a port.

KVM (Keyboard, Video, and Mouse) switch

Hardware device that enables multiple computers to be viewed and controlled by a single mouse, keyboard, and screen.

service menu

Hidden device menu containing tools for technicians servicing the device. May contain diagnostics, reports, or interfaces for changing otherwise inaccessible settings.

Diagnostics menu

Hidden mobile device menu that contains tests and diagnostics for verifying the functionality of various device hardware.

FAT (File Allocation Table)

Hidden table that records how files on a hard disk are stored in distinct clusters; the only way DOS knows where to access files. Address of first cluster of a file is stored in the directory file. FAT entry for the first cluster is the address of the second cluster used to store that file. In the entry for the second cluster for that file is the address for the third cluster, and so on until the final cluster, which gets a special end-of-file code. There are two FATs, mirror images of each other, in case one is destroyed or damaged. Also refers to the 16-bit file allocation table when used by Windows 2000 and later NT-based operating systems.

S/PDIF (Sony-Philips Digital Interface)

High-Quality digital audio connector. Users can connect their computers directly to a 5.1 speaker system or receiver with a single cable. S/PDIF comes in both a coaxial version and an optical version

audio interface

High-end external sound device used by Audio engineers and recording artists.

quick format

High-level formatting that creates just the file allocation table and a blank root directory

DSL (digital subscriber line)

High-speed Internet connection technology that uses a regular telephone line for connectivity. DSL comes in several varieties, including asynchronous (ADSL) and synchronous (SDSL), and many speeds. Typical home-user DSL connections are ADSL with faster download speeds than upload speeds.

fiber-optic cable

High-speed cable for transmitting data, made of high-purity glass sealed within an opaque tube. Much faster than conventional copper wire such as coaxial cable. Most common connectors include ST, SC, and LC

print resolution

How densely a printer lays down ink on the page. Measured in "dots per inch" (dpi). Affects quality of a print image

file format

How information is encoded in a file. Two primary types are binary (pictures) and ASCII (text), but within those are many formats, such as BMP and GIF for pictures. Commonly represented by a suffix at the end of the filename; for example, .txt for a text file or .exe for an executable.

TrackPoint

IBM's pencil eraser-sized joystick used in place of a mouse on laptops.

IEEE 1394

IEEE standard governing FireWire communication. see FireWire

link-local address

IPv6 address a computer gives itself when it first boots. IPv6's equivalent to IPv4's APIPA address

VR headset

Immersive headset or eyewear that enables its wearer to interact with simulated reality

PATA (Parallel ATA)

Implementation that integrates the controller on the disk drive itself. (See also ATA, IDE, SATA.)

Safe mode

Important diagnostic boot mode for Windows that runs only very basic drivers and turns off virtual memory.

Enhanced 911 (E-911)

Improves 911 service for cellular phones by using GPS and cellular network triangulation to locate the device and dispatch emergency responders

kill

In UNIX shells (such as Bash) and in PowerShell. this command terminates the indicated process

charms

In Windows 8 and 8.1, tools located in the hidden Charms bar, such as a search function, a sharing tool, a settings tool, and more.

Storage Spaces

In Windows 8 and later, a software RAID solution that enables users to group multiple drives into a single storage pool

Personalization applet

In Windows 8.1 and earlier, this Control Panel applet handles user preferences such as the background picture, colors of various interface elements, and so on.

default gateway

In a TCP/IP network, the nearest router to a particular host. This router's IP address is part of the necessary TCP/IP configuration for communicating with multiple networks using IP

work area

In a basic structured cabling network, often simply an office or cubicle that potentially contains a PC attached to the network

owner

In both NTFS and UNIX permissions, the owner is usually the user that created a given file or folder, although both systems support changing ownership to another user

backout plan

In case a change doesn't go as planned, a set of steps necessary to undo the change and restore the infrastructure to its previous state.

System resources

In classic terms, the I/O addresses, IRQs, DMA channels, and memory addresses. Also refers to other computer essentials such as hard drive space, system RAM, and processor speed

pixel (picture element)

In computer graphics, smallest element of a display space that can be independently assigned color or intensity.

anti-aliasing

In computer imaging, blending effect that smooths sharp contrasts between two regions e.g. jagged lines or different colors. Reduces jagged edges of text or objects. In voice signal processing, process of removing or smoothing out spurious frequencies from wave forms produced by converting digital signals back to analog

transfer roller

In more recent laser printers, replaces the transfer corona, but performs the same task: applying a positive charge to the paper to draw toner form the imaging drum to the papaer

Port (networking)

In networking, the number used to identify the requested service (such as SMTP or FTP) when connecting to a TCP/IP host. Examples: 80 (http), 443 (HTTPS), 21 (FTP), 23 (Telnet), 25 (SMTP), 110 (POP3), 143 (IMAP), and 3389 (RDP).

high gloss

Laptop screen finish that offers sharper contrast, richer colors, and wider viewing angles than a matte finish, but is also much more reflective.

northbridge

In older chipsets, a chip that connects a CPU to memory, the PCI bus, Level 2 cache, and high-speed graphics. Communicates with the CPU through the frontside bus. Newer CPUs feature an integrated northbridge

Southbridge

In older chipsets, a chip that handled all the inputs and outputs to the many devices in the PC

trigger port

In port triggering, outbound traffic on this port will cause the router to open the destination port and wait for a response

string

In programming and scripting, a non-numeric sequence of alphanumeric data

variables

In scripting and programming, named labels for some portion of in-memory data. The actions taken by the script or program may change or replace the data in the variable

incident response leader

In some organizations, a person other than a supervisor responsible for receiving a responding to all incident reports.

DVD-RW/DVD+RW

Incompatible rewritable DVD media formats.

bit depth

Indicates the number of signal characteristics a device can capture or produce, or the number recorded in a file. Greater bit depths mean more characteristics can be captured, stored, and reproduced. Often used to describe the quality of audio or video signals.

ASCII (American Standard Code for Information Interchange)

Industry-standard 8-bit characters used to define text characters, consisting of 96 upper- and lowercase letters, plus 32 non printing control characters each of which is numbered. These numbers were designed to achieve uniformity among computer devices for printing and the exchange of simple text documents

CompTIA Network+ certification

Industry-wide, vendor-neutral certification for network technicians, covering network hardware, installation, and troubleshooting.

CompTIA A+ certification

Industry-wide, vendor-neutral computer certification program that demonstrates competency as a computer technician

surge suppressor

Inexpensive device that protects your computer from voltage spikes.

BSoD (Blue Screen of Death)

Infamous error screen that appears when Windows encounters an unrecoverable error.

location data

Information provided by a mobile device's GPS; used for mapping functions as well as for location-aware services, such as finding nearby restaurants or receiving coupons for nearby shops.

SPD (serial presence detect)

Information stored on a RAM chip that describes the speed, capacity, and other aspects of the RAM chip.

mouse

Input device that enables users to manipulate a cursor on the screen to select items.

keyboard

Input device. Three common types of keyboards exist: those that use a mini-DIN (PS/2) connection, those that use a USB connection, and those that use wireless technology.

multitouch

Input method on many smartphones and tablets that enables you to use multiple fingers to do all sorts of fun things, such as using two fingers to scroll or swipe to another screen or desktop.

upgrade installation

Installation of Windows on top of an earlier installed version, thus inheriting all previous hardware and software settings.

Android application package (APK)

Installation software for Android apps

clean installation

Installing an operating system on a fresh drive, following a reformat of that drive. often it's the only way to correct a problem with a system when many of the crucial operating system files have become corrupted.

USB host controller

Integrated circuit that is usually built into the chipset that acts as the interface between the system and every USB device that connects to it

Hyper-Threading

Intel CPU feature (generically called simultaneous multithreading) that enables a CPU to run more than one thread at once

Platform Controller Hub (PCH)

Intel's name for the chip that collects functions once performed by multiple chips known as the chipset

session hijacking

Intercepting a valid computer session to get authentication information from it, enabling the attacker to use whatever resources the authentication grants access for as long as the authentication information or session is valid

FireWire (IEEE 1394)

Interconnection standard to send wide-band signals over a serialized, physically thin connector system. Serial bus developed by Apple and Texas Instruments; enables connection of 63 devices at speeds up to 800 Mbps. Mostly supplanted by Thunderbolt

MIDI (Musical Instrument Digital Interface)

Interface between a computer and a device for simulating musical instruments. Rather than sending large sound samples, a computer can simply send "instructions" to the instrument describing pitch, tone, and duration of a sound. MIDI files are therefore very efficient. Because a MIDI file is made up of a set of instructions rather than a copy of the sound, modifying each component of the file is easy. Additionally, it is possible to program many channels, or "voices," of music to be played simultaneously, creating symphonic sound.

recent apps

Interface for viewing a list of recently used apps on a mobile device

Network

Interface in File Explorer or Windows Explorer; displays networked computers and other devices, such as network printers

GUI (Graphical User Interface)

Interface that allows users to interact with computer graphically, by using a mouse or other pointing device to manipulate icons that represent programs or documents. Instead of using only text as in early interfaces. Pronounced "gooey"

IPv4 (Internet Protocol version 4)

Internet standard protocol that provides a common layer over dissimilar networks; used to move packets among host computers and through gateways if necessary. Part of the TCP/IP protocol suite. Uses the dotted-decimal format—xxx.xxx.xxx.xxx. Each x represents an 8-bit binary number, or 0-255. Here's an example 192.168.4.1

Spotify

Internet streaming music service

Ars Technica (arstechnica.com)

Internet technology news site.

Cloud file storage services

Internet-based shared file storage spaces that enable users to save, edit, share, and collaborate on stored files, as well as synchronize files among multiple devices and users

NMI (non-maskable interrupt)

Interrupt code sent to the processor that cannot be ignored. Typically manifested as a BSoD.

asset tag

Inventory tracking tags (which may be simple barcodes or use wireless networking protocols such as RFID) that help an organization track items such as equipment.

pop-up

Irritating browser window that appears automatically when you visit a Web site.

Knowledge Base

Large collection of documents and FAQs that is maintained by Microsoft. Found on Microsoft's Web site, the Knowledge Base is an excellent place to search for assistance on most operating system problems.

personal safety

Keeping yourself away from harm.

Windows logo key

Key on a keyboard bearing the Windows logo that traditionally brings up the Start menu, but is also used in some keyboard shortcuts.

password

Key used to verify a user's identity on a secure computer or network

local area network

LAN

PostScript

Language defined by Adobe Systems, Inc., for describing how to create an image on a page. The description is independent of the resolution of the device that will actually create the image. It includes a technology for defining the shape of a font and creating a raster image at many different resolutions and sizes.

matte

Laptop screen finish that offers a good balance between richness of colors and reflections, but washes out in bright light.

static charge eliminator

Laser printer component that removes the static charge from paper to prevent the paper from wrapping around the imaging drum

IEEE (Institute of Electrical and Electronics Engineers)

Leading standards-setting group in the United States

trusted source

Legitimate app stores run by the major OS vendors such as Applie, Google, Microsoft, and Amazon

tiers

Levels of Internet providers, ranging from the Tier 1 backbones to Tier 3 regional networks.

Certification

License that demonstrates competency in some specialized skill.

lamp

Light source in a projector

CCFL (cold cathode fluorescent lamp)

Light technology used in older LCDs and flatbed scanners. CCFLs use relatively little power for the amount of light they provide

Xeon

Line of Intel CPUs designed for servers

vi

Linux and macOS command-line tool for editing text files

passwd

Linux command for changing a user's password

dd

Linux command for copying entire block volumes.

rm

Linux command for deleting files

ifconfig

Linux command for finding out a computer's IP address information

sudo

Linux command for gaining root access

apt-get

Linux command for installing or updating a program using the advanced packaging tool.

Users group

List of local users not allowed, among other things, to edit the Registry or access critical system files. They can create groups, but can only manage the groups they create.

Administrators group

List of members with complete administrator privileges

local user account

List of user names and their associated passwords with access to a system, contained in an encrypted database.

Search box

Location on the Windows 10 Taskbar where users can input text and see suggestions (for settings, programs, files, and popular Web searches) that may be related

Recycle Bin

Location to which files are moved when they are deleted from a modern Windows system. To permanently remove files from a system, they must be emptied from the Recycle Bin.

network ID

Logical number that identifies the network on which a device or machine exists.This number exists in TCP/IP and other network protocol suites

global user account

Login information and associated settings maintained at a location accessible by any computer, irrespective of location or local account configuration

Welcome screen

Logon screen for Windows. Enables users to select their particular user account by clicking on their user picture.

SCSI (Small Computer System Interface)

Long-lived storage device technology once common in the server market. Has been through many iterations. Today, the SCSI command set lives on in Serial Attached SCSI (SAS) hard drives

shoulder surfing

Looking for credentials or sensitive information by watching someone use a computer or device, often over their shoulder

control construct

Loops and conditional statements (such as the "if" statement) are examples of control constructs, which enable programmers to control the conditions user which certain sections of code will run

DDR3L

Low-voltage version of DDR3. Provides cost savings in large deployments, such as a data center

Celeron

Lower-cost brand of Intel CPUs.

Disk Utility

Mac OS X tool that checks for hard drive errors

Finder

Mac OS X's file and folder browser.

dedicated server

Machine that is not used for any client functions, only server functions.

sector

Magnetically preset storage areas on traditional magnetic hard drives. On older hard drives, a sector held 512 bytes of data; modern drives use 4096-byte Advanced Format (AF) sectors

system unit

Main component of the PC, in which the CPU, RAM, CD-ROM, and hard drive reside. All other devices—the keyboard, mouse, and monitor—connect to the system unit.

SMTP (Simple Mail Transfer Protocol)

Main protocol used to send electronic mail on the Internet. Uses port 25

encryption

Making data unreadable by those who do not possess a key or password.

Verify full system functionality and, if applicable, implement preventive measures.

Making sure that a problem has been resolved and will not return (Step 5 of 6 in the CompTIA troubleshooting methodology)

file-level backup

Manually or automatically copying individual files or folders to one or more backup locations

static IP address

Manually set IP address that will not change

EIDE (Enhanced IDE)

Marketing concept of hard drive-maker Western Digital, encompassing four improvements for IDE drives, including drives larger than 528 MB, four devices, increase in drive throughput, and non-hard drive devices. see also ATAPI

PVC (polyvinyl chloride)

Material used to make the plastic protective sheathing around many basic network cables. Produces noxious fumes when burned

consumables

Materials used up by printers, including paper, ink, ribbons, and toner cartridges.

direct LED backlighting

Matrix of LEDs that illuminates a display from directly behind the display panel

interface

Means by which a user interacts with a piece of software

assertive communication

Means of communication that is not pushy or bossy but is also not soft. Useful in dealing with upset customers as it both defuses their anger and gives them confidence that you know what you're doing.

group policy

Means of easily controlling the settings of multiple network clients with policies such as setting minimum password length or preventing Registry edits.

voucher

Means of getting a discount on the CompTIA A+ exams.

shared memory

Means of reducing the amount of memory needed on a video card by borrowing from the regular system RAM, which reduces costs but also decreases performance.

resolution

Measurement for monitors and printers expressed in horizontal and vertical dots or pixels. Higher resolutions provide sharper details and thus display better-looking images

wattage (watts or W)

Measurement of the amps and volts needed for a particular device to function.

volts (V)

Measurement of the pressure of the electrons passing through a wire, or voltage

duplexing assembly

Mechanical feature of some printers that can automatically flip the paper to print on both sides

fuser assembly

Mechanism in laser printers that uses two rollers to fuse toner to paper during the print process.

boot method

Media a computer uses to initiate the booting process. Includes optical media, removable drives, or a networked location. For the related CMOS setting, see boot sequence

IMC (integrated memory controller)

Memory controller circuitry built into the CPU that enables faster control over things like the large L3 cache shared among multiple cores.

RAM (Random Access Memory)

Memory that can be accessed at random—that is, memory which you can write to or read from without touching the preceding address. This term is often used to mean a computer's main memory.

volatile

Memory that must have constant electricty to retain data.

SO-DIMM (small outline DIMM)

Memory used in portable PCs because of its small size

DRAM (Dynamic Random Access Memory)

Memory used to store data in most personal computers. DRAM stores each bit in a "cell" composed of a transistor and a capacitor. Because the capacitor in a DRAM cell can only hold a charge for a few milliseconds, DRAM must be continually refreshed, or rewritten, to retain its data

Start menu

Menu that can be accessed by clicking the Start button on the Windows taskbar. Enables you to see all pro- grams loaded on the system and to start them.

e-mail (electronic mail)

Messages, usually text, sent from one person to another via computer. Can also be sent automatically to a group of addresses (mailing list).

slot covers

Metal plates that cover up unused expansion slots on the back of a PC. Useful in maintaining proper airflow through a computer case.

hierarchical directory tree

Method by which Windows organizes files into a series of folders, called directories, under the root directory. (See also root directory.)

RAID (redundant array of independent disks)

Method for creating a fault-tolerant storage system. RAID uses multiple hard drives in various configurations to offer differing levels of speed/data redundancy

disk striping with parity

Method for providing fault tolerance by writing data across multiple drives and then including an additional drive, called a parity drive, that stores information to rebuild the data contained on the other drives. Requires at least three physical disks: two for the data and a third for the parity drive. This provides data redundancy at RAID levels 5, 10, and 0+1 with different options.

MAC address filtering

Method of limiting wireless network access based on the physical, hard-wired address of the wireless NIC of a computing device.

Run as administrator

Method of running a Windows program with elevated privileges, disabling protections that normally limit a program's ability to damage the system

CFS (Central File System)

Method to unify all storage devices within a network or organization to facilitate a single management point and to provide user access to any file or data within the organization.

Windows Update

Microsoft application used to keep Windows operating systems up to date with the latest patches or enhancements.

IPSec (Internet Protocol Security)

Microsoft's encryption method of choice for networks consisting of multiple networks linked by a private connection, providing transparent encryption between the server and the client.

Windows Hardware Certification Program

Microsoft's rigorous testing program for hardware manufacturers, which hardware devices must pass before their drivers can be digitally signed.

page fault

Minor memory-addressing error.

brightness contorl

Mobile device feature controlling screen brightness. Can be set to automatically adjust to ambient light or be manually changed

location services

Mobile device feature that can detect the device's location, enabling apps to request and use this information to provide location-aware services, such as finding nearby restaurants

Wi-Fi calling

Mobile device feature that enables users to make voice calls over a Wi-Fi network, rather than a cellular network.

screen lock

Mobile device feature that locks the screen until some form of authentication challenge is passed

passcode lock

Mobile device security feature that requires you to type in a series of letters, numbers, or motion patterns to unlock the mobile device each time you press the power button.

e-reader

Mobile electronic device used for reading e-books

NFC (Near Field Communication)

Mobile technology that enables short-range wireless communication between mobile devices. Now used for mobile payment technology such as Apple Pay and Google Pay

airplane mode

Mode for mobile devices that disables all wireless and cellular communication for use on airplanes

AT (Advanced Technology)

Model name of the second-generation, 80286-based IBM computer. Many aspects of the AT, such as the BIOS, CMOS, and expansion bus, have become de facto standards in the PC industry. The physical organization of the components on the motherboard is called the AT form factor.

UEFI (Unified Extensible Firmware Interface)

Modern 32- or 64-bit firmware programming interface. Replaced the original 16-bit PC BIOS. UEFI supports large capacity storage drives, additional features, and a more direct booting process

touchscreen

Monitor with a type of sensing device across its face that detects the location and duration of contact, usually by a finger or stylus.

S.M.A.R.T. (Self-Monitoring Analysis and Reporting Technology)

Monitoring system built into hard drives that tracks errors and error conditions within the drive

Phillips head screwdriver

Most important part of a PC tech's toolkit

flatbed scanner

Most popular form of consumer scanner; runs a bright light along the length of the tray to capture an image.

FlexATX

Motherboard form factor. Motherboards built in accordance with the FlexATX form factor are very small, much smaller than microATX motherboards.

inheritance

NTFS feature that passes on the same permissions in any subfolders/files resident in the original folder

filename

Name assigned to a file when the file is first written on a disk. Every file on a disk within the same folder must have a unique name. Filenames can contain any character (including spaces), except the following: \ / : * ? " < > |

Ethernet

Name coined by Xerox for the first standard of network cabling and protocols that define everything necessary to get data from one computer to another. Since its inception, Ethernet has gone through hundreds of improvements and even forms the basis of wireless networking signals

DE (desktop environment)

Name for the various user interfaces found in Linux distributions.

Pentium

Name given to the fifth and later generations of Intel microprocessors; original had a 32-bit address bus, 64-bit external data bus, and dual pipelining. Also used for subsequent generations of Intel processors—the Pentium Pro, Pentium II, Pentium III, and Pentium 4. Currently used as a budget label for Intel CPUs.

Core

Name used for the family of Intel CPUs that succeeded the Pentium 4, such as the Core i3, core i5, and core i7

code names

Names that keep track of different variations within CPU models

Network File System (NFS)

Network file and print sharing protocol for UNIX and Linux systems that competed with Server Message Block (SMB). Usage has declined as SMB won out

peer-to-peer network

Network in which each machine can act as both a client and a server.

botnet

Network of computers infected with malware that can be controlled to do the bidding of the malware developers, or anyone who pays them. A common use is carrying out distributed denial of service (DDoS) attacks

domain-based network

Network that eliminates the need for logging on to multiple servers by using domain controllers to hold the security database for all systems.

mesh topology

Network topology where each computer has a dedicated line to every other computer, most often used in wireless networks.

mail server

Networked host or server that provides e-mail service

CSMA (Carrier Sense Multiple Access/collision avoidance)

Networking scheme used by wireless devices to transmit data while avoiding data collisions, which wireless nodes have difficulty detecting

cellular wireless networks

Networks that enable cell phones, smartphones, and other mobile devices to connect to the Internet.

Multiuser MIMO (MU-MIMO)

New version of MIMO included in 802.11ac that enables a WAP to broadcast to multiple users simultaneously

Computing Technology Industry Association (CompTIA)

Nonprofit IT trade association that administers the CompTIA +A and Network+ exams and many other vendor neutral IT certifications

hang time

Number of seconds a too-often-hung computer is airborne after you have thrown it out a second-story window.

binary numbers

Number system with a base of 2, unlike the number systems most of us use that have bases of 10 (decimal numbers), 12 (measurement in feet and inches), and 60 (time). Binary numbers are preferred for computers for precision and economy. An electronic circuit that can detect the difference between two states (on-off, 0-1) is easier and more inexpensive to build than one that could detect the differences among ten states (0-9).

grayscale depth

Number that defines how many shades of gray the scanner can save per dot.

IP address

Numeric address of a computer connected to the Internet. An IPv4 address is made up of four octets of 8-bit binary numbers translated into their shorthand numeric values. An IPv6 address is 128 bits long. The IP address can be broken down into a network ID and a host ID. Also called Internet address

multiboot installation

OS installation in which multiple operating systems are installed on a single machine.

toner cartridge

Object used to store the toner in a laser printer. (See also laser printer, toner.)

hang

Occurs when a computer or program stops responding to keyboard commands or other input; a computer or program in such a state is said to be 'hung'

Component failure

Occurs when a system device fails due to a manufacturing or some other type of defect.

fragmentation

Occurs when files and directories get jumbled on a fixed disk and are no longer contiguous. Can significantly slow down hard drive access times and can be repaired by using the defrag utility included with each version of Windows. (See also defragmentation.)

nbtstat

Old command-line utility predating Windows. Provides information on NetBIOS. While not as useful as it once was, it can still help troubleshoot small workgroups.

TN (twisted nematic)

Older technology for LCD monitors. TN monitors produce a decent display for a modest price, but they have limited viewing angles and can't accurately reproduce all the color information sent by the video card.

active partition

On a hard drive, primary partitions that contains an operating system

backside bus

On older CPUs, a set of wires that connected the CPU to Level 2 cache. First appeared in the Intel Pentium Pro. See also frontside bus and external data bus

frontside bus

On older PC architectures, the wires that connect the CPU to its external memory controller

baud

One analog cycle on a telephone line. In the early days of telephone data transmission, the baud rate was often analogous to bits per second. Due to advanced modulation of baud cycles as well as data compression, this is no longer true.

Certified Cisco Network Associate (CCNA)

One of the certifications demonstrating a knowledge of Cisco networking products.

Personal Digital Assistant (PDA)

One of the earliest mobile devices. Lacked cellular connections and touch interfaces, but still shared basic features with current mobile devices

NVIDIA Corporation

One of the foremost manufacturers of graphic cards and chipsets

POP3 (Post Office Protocol 3)

One of the two protocols that receive e-mail from SMTP servers. POP3 uses TCP port 110. While historically most e-mail clients used this protocol, the IMAP 4 e-mail protocol is now more common

command mode

One of two modes (along with insert mode) used in vi. Enables inputting commands such as copy or paste, see vi

OpenGL

One of two popular APIs used today for video cards. Originally written for UNIX systems but now ported to Windows and Apple systems. (See also DirectX.)

Protected Health Information (PHI)

Personally identifiable information that includes an individual's medical and health history.

storage pool

One or more physical drives grouped into a single Storage Space

theory of probable cause

One possible reason why something is not working; a guess.

mini connector

One type of power connector from a PC power supply unit. Supplies 5 and 12 volts to peripherals. Also known as a floppy connector.

Linux

Open-source UNIX-clone operating system.

Windows 10

Operating system developed by Microsoft that powers most desktop and portable computers in use today

Windows Vista

Operating system developed by Microsoft. Version of Windows; came in many different editions for home and office use, but did not have a server edition. Succeeded by Windows 7. No longer supported

Windows 7

Operating system developed by Microsoft. Version of Windows; comes in many different editions for home and office use, but does not have a server edition. Succeeded by Windows 8/8.1

macOS

Operating system from Apple that powers their desktop and portable computers. Based on UNIX; macOS runs on Intel/IBM-based hardware, just like Microsoft Windows. Before 2016, it was known as OS X

image deployment

Operating system installation that uses a complete image of a hard drive as an installation media. Helpful when installing an operating system on a large number of identical PCs.

OS X

Operating system on older Macintosh computers. Based on a UNIX core, early versions of OS X ran on Motorola-based hardware; later versions ran on Intel-based hardware. The X is pronounced "ten" rather than "ex" renamed macOS in 2016

Windows 8/8.1

Operating systems developed by Microsoft. Versions of Windows noted for the Metro interface. Used for desktop and portable PCs and for mobile devices. Succeeded by windows 10

DVD (digital versatile disc)

Optical disc format that provides for 4-17 GB of video or data storage.

Blu-ray Disc (BD)

Optical disc format that stores up to 100 GB of data, designed as a replacement media for DVD. Competed with HD DVD

End Process Tree

Option in Task Manager to halt a program or background process and all of its supporting processes

Last Known Good Configuration

Option on the Advanced Startup Options menu that enables your system to revert to a previous configuration to troubleshoot and repair any major system problems.

CD (compact disc)

Originally designed as the replacement for vinyl records, but (along with other optical media) is also useful for long-term storage of music and data

CMOS (complementary metal-oxide semiconductor)

Originally, computer systems had a standalone CMOS chip - a tiny bit RAM hooked up to a small battery that enabled it to hold system settings for the BIOS firmware even with the computer off. This had long since been incorporated into the chipset. CMOS is often informmally used to refer to the CMOS setup program or system setup utility

printer

Output device that can print text or illustrations on paper. Microsoft uses the term to refer to the software that controls the physical print device.

40-pin ribbon cable

PATA cable used to attach EIDE devices (such as hard drives) or ATAPI devices (such as optical drives) to a system See SATA

webcam

PC camera most commonly used for Internet video.

IDE (Integrated Drive Electronics)

PC specification for small- to medium-sized hard drives in which the controlling electronics for the drive are part of the drive itself, speeding up transfer rates and leaving only a simple adapter (or "paddle"). IDE only supported two drives per system of no more than 504 MB each, and has been completely supplanted by Enhanced IDE. EIDE supports four drives of over 8 GB each and more than doubles the transfer rate. The more common name for PATA drives. Also known as intelligent drive electronics. (See PATA.)

jumper

Pair of small pins that can be shorted with a shunt to configure many aspects of PCs. Often used in configurations that are rarely changed, such as master/slave settings on IDE drives.

SSID (Service Set Identifier)

Parameter used to define a wireless network; otherwise known as the network name.

jack (physical connection)

Part of a connector into which a plug is inserted. Also referred to as a port.

port (physical connection)

Part of a connector into which a plug is inserted. Physical ports are also referred to as jacks.

Actively listen

Part of respectful communication involving listening and taking notes without interrupting

HAL (hardware abstraction layer)

Part of the Windows OS that separates system-specific device drivers from the rest of the OS

USB root hub

Part of the host controller that makes the physical connection to the USB ports.

primary partition

Partition on a Windows hard drive that can store a bootable operating system.

globally unique identified (GUID) partition table (GPT)

Partitioning scheme that enables you to create more than four primary partitions without need to use dynamic disks

virus shield

Passive monitoring of a computer's activity, checking for viruses only when certain events occur, such as a program execution or file download

strong password

Password containing at least eight characters, including letters, numbers, and non-alphanumeric symbols

thermal paste

Paste-like material with very high heat-transfer properties. Applied between the CPU and the cooling device, it ensures the best possible dispersal of heat from the CPU. Also called heat dope or thermal compound

raster image

Pattern of dots representing what the printed page should look like

BitTorrent

Peer-to-peer file-sharing program

maintenance

Period jobs that should be done to keep an operating system running well

hardware

Physical computer equipment such as electrical, electronic, magnetic, and mechanical devices. Anything in the computer world that you can hold in your hand. A hard drive is hardware; Microsoft Word is not

device charger

Plugs into a power source and charges a device through one of its ports, such as USB or Lightning. Convenient for charging while the device stays on.

battery charger

Plugs into a power source and directly charges a device battery. Most convenient with a spare battery, since it requires removing the battery to charge it.

optical mouse

Pointing device that uses light rather than electronic sensors to determine movement and direction the mouse is being moved.

ATX (Advanced Technology Extended)

Popular motherboard form factor that generally replaced the AT form factor.

UTP (Unshielded Twisted Pair)

Popular type of cabling for telephone and networks, composed of pairs of wires twisted around each other at specific intervals. The twists serve to reduce interference (also called crosstalk). The more twists, the less interference. Unlike its cousin, STP, UTP cable has no metallic shielding to protect the wires from external interference. 1000BaseT uses UTP, as do many other networking technologies. UTP is available in a variety of grades, called categories, as follows: CAT 1 UTP Regular analog phone lines—not used for data communications. CAT 2 UTP Supports speeds up to 4 Mbps. CAT 3 UTP Supports speeds up to 16 Mbps. CAT 4 UTP Supports speeds up to 20 Mbps. CAT 5 UTP Supports speeds up to 100 Mbps. CAT 5e UTP Supports speeds up to 1000 Mbps. CAT 6 UTP Supports speeds up to 10 Gbps. CAT 6a UTP Supports speeds up to 10 Gbps. CAT 7 UTP Supports 10-Gbps networks at 100-meter segments; shielding for individual wire pairs reduces crosstalk and noise problems. CAT 7 is not a TIA /EIA standard.

camcorder

Portable device for recording audio and video. While camcorders originally recorded to tape (first analog, and later digital), most modern digital camcorders record to flash media

external speaker

Portable device that can substantially improve on the audio output of a mobile device or portable computer. Typically connects via Bluetooth or a regular headphone jack

2-in-1

Portable devices that attempt to serve as both a laptop and a tablet

hybrid (portable device)

Portable devices that stuff portable-computer power in mobile device-style form factors, such as a tablet.

virtual memory

Portion of the hard drive set aside by an OS to act like RAM when the system needs more RAM than is installed. A file containing this data is typically called a page file. in Windows and a swap file in UNIX platforms like Linux and macOS

electromagnetic pulse (EMP)

Potentially damaging burst of electromagnetic energy caused by events such as electrostatic discharge (ESD)

sleep mode

Power management setting in which all data from RAM is perserved by powering down much of the computer but maintaining power to RAM, or by writing the contents of RAM to the mass storage drive before the system goes into a reduced-power mode. Upon waking up,, the informaton is retrieved from the HDD or SSD and returned to RAM if necessary; the system continues where it left off

hibernate

Power management setting in which all data from RAM is written to the hard drive before the system goes into sleep mode. Upon waking up, all information is retrieved from the hard drive and returned to RAM. Also called suspend to disk

ACPI (Adanced Configuration and Power Interface)

Power management specification that far suprasses its predecessor, APM, by providing support for hot-swappable devices and better control of power modes

throttling

Power reduction/thermal control capability allowing CPUs to slow down during low activity or high heat build-up situations. Intel's version is known as Speed- Step, AMD's as PowerNow!.

single rail

Power supply configuration where all power is supplied along a single pathway

robocopy

Powerful command-line utility for copying files and directories, even over a network.

subwoofer

Powerful speaker capable of producing extremely low-frequency sounds.

environmental control

Practice of protecting computing equipment from environmental damage by taking measures such as air conditioning, proper ventilation, air filtration, temperature monitoring, and humidity monitoring

power plan

Preconfigured profiles (such as Balanced, High performance, and Power saver) in the Power Options applet that modify a Windows system's behavior to adjust power consumption

giga

Prefix for the quantity 1,073,741,824 bytes, except with hard drive labeling, where it means 1 billion bytes. One gigahertz is 1 billion hertz

mega-

Prefix that stands for the binary quantity 1,048,576 (2^20) or the decimal quantity of 1,000,000. One megabyte is 1,048,576 bytes. One megahertz, however, is a million hertz. Sometime shortened to Meg, as in "a 286 has an address space of 16 Megs"

tera-

Prefix that usually stands for the binary number 1,099,511,627,776 (240). When used for mass storage, it's often shorthand for 1 trillion bytes.

Port Forwarding

Preventing the passage of any IP packets through any ports other than the ones prescribed by the system administrator.

external data bus (EDB)

Primary data highway of all computers. Everything in your computer is tied either directly or indirectly to the external data bus. (See also frontside bus and backside bus.)

system BIOS

Primary set of BIOS stored on a flash ROM chip on the motherboard. Defines the BIOS for all the assumed hardware on the motherboard, such as keyboard controller, floppy drive, basic video, and RAM.

PCL (Printer Command Language)

Printer language created by Hewlett-Packard to supersede simple ASCII codes and used on a broad cross section of printers. Identified as printer control language in CompTIA A+ exam objectives

separation pad

Printer part that uses friction to separate a single sheet from any others the pickup roller grabbed

network printer

Printer that connects directly to a network.

dot-matrix printer

Printer that creates each character from an array of dots. Pins striking a ribbon against the paper, one pin for each dot position, form the dots. May be a serial printer (printing one character at a time) or a line printer.

dye-sublimation printer

Printer that uses a roll of heat-sensitive plastic film embedded with dyes, which are vaporized and then solidified onto specially coated paper to create a high-quality image.

thermal printer

Printer that uses heated printheads to create high-quality images on special or plain paper. Common in retail receipt printers, which use large rolls of thermal paper housed in a feed assembly that automatically draws the thermal receipt paper over the heating element

heating element

Printing component of direct thermal printers. Burn dots into the surface of heat-sensitive thermal paper

XML Paper Specification (XPS) print path

Printing subsystem in Windows. Has enhanced color management and good print layout fidelity

disk striping

Process by which data is spread among multiple (at least two) drives. Increases speed for both reads and writes of data. Considered RAID level 0 be- cause it does not provide fault tolerance.

disk mirroring

Process by which data is written simultaneously to two or more disk drives. Read and write speed is decreased but redundancy in case of catastrophe is increased.

firmware update

Process by which the BIOS of a motherboard can be updated to reflect patched bugs and added features. Performed, usually, through CMOS, though some motherboard manufacturers provide a Windows program for performing a firmware update

rooting

Process for circumventing the security restrictions and gaining access to the root user account on an Android device

jailbreaking

Process for circumventing the security restrictions present on an iOS device

activation (software)

Process of confirming that an installed copy of a Microsoft product (most commonly windows or a Microsoft Office application) is legitimate. Ususally done at the end of software installation

Calibration

Process of matching the print output of a printer to the visual output of a monitor.

incident reporting

Process of reporting gathered data about a system or problem to supervisors. Creates a record of work accomplished, and may help identify patterns. Often documented on an incident report form

multitasking

Process of running multiple programs or tasks on the same computer at the same time.

compression

Process of squeezing data to eliminate redundancies allowing files to use less space when stored or transmitted

burn

Process of writing data to a writable optical disc, such as a DVD-R.

single sign-on (SSO)

Process that uses an account or credentials for a popular service (such as a google account) to sign on or authenticate with other services

autodetection

Process through which new disks are automatically recognized by the BIOS.

escalate

Process used when a person assigned to repair a problem is not able to get the job done, such as sending the problem to someone with more expertise

pipeline

Processing methodology where multiple calculations take place simultaneously by being broken into a series of steps. Often used in CPUs and video processors.

hardware virtualization support

Processor features that speed up and simplify virtualization. Required for some hypervisors to function

Web browser

Program designed to retrieve, interpret, and display Web pages.

CMOS setup program

Program enabling you to access and update CMOS data. Also referred to as the system setup utility, BIOS setup utility, UEFI/BIOS setup and similar names.

TWAIN (technology without an interesting name)

Programming interface that enables a graphics application, such as a desktop publishing program, to activate a scanner, frame grabber, or other image-capturing device. Default driver type for scanners

Component Services

Programming tools in Windows for the sharing of data objects between programs.

CNR (communications and networking riser)

Proprietary slot used on some motherboards to provide a connection for modems, sound cards, and NICs that is free from sound interference

Z-Wave

Proprietary wireless networking protocol (with an open API for programmers) designed to address home automation challenges

safety goggles

Protective glasses that keep stuff out of your eyes.

system lockout

Protects against attempts to brute-force a lock screen or login system by locking the user out until they perform some more thorough authentication process. Occurs when too many consecutive login attempts fail.

Virtual Network Computing (VNC)

Protocol enabling remote desktop connections

Service Location Protocol (SLP)

Protocol for advertising and discovering available services over a network. Most common with Print devices. Uses TCP/UDP port 427

ARP (Address Resolution Protocol)

Protocol in the TCP/IP suite used with the command-line utility of the same name (arp) to determine the MAC address that corresponds to a particular IP address.

IPv6 (Internet Protocol version 6)

Protocol in which addresses consist of eight sets of four hexadecimal numbers, each number being a value between 0000 and FFFF, using a colon to separate the numbers. Here's an example: FEDC:BA98:7654:3210:0800:200C:00CF:1234.

DHCP (Dynamic Host Configuration Protocol)

Protocol that enables client hosts to request and receive TCP/IP settings automatically from an appropriately configured server. Uses UDP ports 67 and 68

IrDA (Infrared Data Association)

Protocol that enables communication through infrared devices, which speeds of up to 4 Mbps

NetBIOS (Network Basic Input/Output System)

Protocol that operates at the Session layer of the OSI seven-layer model. This protocol creates and manages connections based on the names of the computers involved. Uses TCP ports 137 and 139, and UDP ports 137 and 138

Lightweight Directory Access Protocol (LDAP)

Protocol used by many operating systems and applications to access directories.

Remote Desktop Protocol (RDP)

Protocol used for Microsoft's Remote Desktop tool. Uses port 3389

P4 power connector

Provides additional 12-volt power to assist the 20/24-pin P1 motherboard power connector

P1 power connector

Provides power to ATX motherboards; 20-pin with original ATX motherboards, 24-pin on current units.

power supply unit (PSU)

Provides the electrical power for a PC. Converts standard AC power into various voltages of DC electricity in a PC

Unified Threat Management (UTM)

Providing robust network security by integrating traditional firewalls with many other security services such as IPS, VPN, load balancing, anti-malware, and more

timbre

Qualities that differentiate the same note played on different instruments

striped volume

RAID 0 volumes. Data is spread across two drives for increased speed.

double-sided RAM

RAM stick with RAM chips soldered to both sides of the stick. May only be used with motherboards designed to accept double-sided RAM. Very common.

ECC RAM/DRAM (error correction code RAM/DRAM)

RAM that uses special chips to detect and fix memory errors. Commonly used in high-end servers where data integrity is crucial

unbuffered RAM

RAM without a register to act as a buffer between the DIMM and memory controller, in other words, normal, consumer-grade RAM

flash ROM

ROM technology that can be electrically reprogrammed while still in the PC. Overwhelmingly the most common storage medium of BIOS in computers today, as it can be upgraded without a need to open the computer on most systems.

DMA controller

Resides between the RAM and the devices and handles DMA requests.

optical resolution

Resolution a scanner can achieve mechanically. Most scanners use software to enhance this ability.

native resolution

Resolution on an LCD monitor that matches the physical pixels on the screen

data usage limit

Restrictions on how much data a user may consume. Once the user exceeds the limit, data may be blocked entirely or bandwidth may be throttled

NTFS permissions

Restrictions that determine the amount of access given to a particular user on a system using NTFS.

factory reset

Returns a device's software to how it left the factory by removing all user-installed data, programs, and customizations.

USB Type-C (connector)

Reversible USB type cable that supports USB Super- Speed+ USB 3.1 with a top speed of 10 Gbps. Quickly becoming the de facto standard port on Android devices. Thunderbolt-enabled USB Type-C ports can reach top speeds of 40 Gbps

NTFS (New Technology File System)

Robust and secure file system introduced by Microsoft with Windows NT. NTFS provides an amazing array of configuration options for user access and security. Users can be granted access to data on a file-by-file basis. NTFS enables object-level security, long filename support, compression, and encryption.

path

Route the operating system must follow to find an executable program stored in a subfolder

Quality of Service (QoS)

Router feature used to prioritize access to network resources. Ensures certain users, applications or services are prioritized when there isn't enough bandwidth to go around by limiting the bandwidth for certain types of data based on application protocol, the IP address of a computer, and all sorts of other features.

port triggering

Router function that enables a computer to open an incoming connection to one computer automatically based on a specific outgoing connection.

FTP (File Transfer Protocol)

Rules that enable two computers to talk to one another during a file transfer. Protocol used when you transfer a file from one computer to another across the Internet. FTP uses port numbers 20 and 21.

emergency repair disk (ERD)

Saves critical boot files and partition information and is the main tool for fixing boot problems in older versions of Windows. Newer versions of Windows call this a system repair disc (Windows Vista/7) or recovery drive (Windows 8/8.1 and 10).

data storage

Saving a permanent copy of your work so that you can come back to it later

file system

Scheme that directs how an OS stores and retrieves data on and off a drive; FAT32 and NTFS are both file systems. Used interchangeably with the term "data structure." (See also data structure.)

data structure

Scheme that directs how an OS stores and retrieves data on and off a drive. Used interchangeably with the term file system. (See also file system.)

monitor

Screen that displays data from a PC. Typically a flat-panel display, such as an LCD

Level 2 (L2) cache

Second RAM cache accessed by the CPU. Much larger and often slower than the L1 cache, and accessed only if the requested program/data is not in the L1 cache.

NLX

Second form factor for slimline systems. Replaced the earlier LPX form factor. (CompTIA lists NLX as New Low-profile Extended)

partition

Section of the storage area of a hard disk. Created during initial preparation of the hard disk, before the disk is formatted

logical drives

Sections of an extended partition on a hard drive that are formatted and (usually) assigned a drive letter, each of which is presented to the user as if it were a separate drive.

HTTPS (HTTP over Secure Sockets Layer)

Secure form of HTTP used commonly for Internet business transactions or any time when a secure connection is required. Uses port 443. (See also HTTP.)

SFTP (Secure File Transfer Protocol)

Secure version of the File Transfer Protocol

access control

Security concept using physical security, authentication, users and groups, and security policies

LoJack

Security feature included in some BIOS/UEFI that enables a user to track the location of a stolen PC, install a key logger, or remotely shut down the stolen computer.

SSL (Secure Sockets Layer)

Security protocol used by a browser to connect to secure Web sites. replaced by Transport Layer Security (TLS))

share-level security

Security sytem in which each resource has a password assigned to it; access to the resource is based on knowing the password

Augmented Reality

See AR

bootstrap loader

Segment of code in a system's BIOS that scans for an operating system, looks specifically for a valid boot sector, and, when one is found, hands control over to the boot sector; then the bootstrap loader removes itself from memory

on-demand

Self-service characteristic of cloud computing. Describes the customer's ability to set up, modify, and delete cloud resources (such as servers, storage, or databases) as needed

rails

Separate DC voltage paths within an ATX power supply.

gearbox

Separate units or packages, also called gear packs, that combine multiple gears for performing mechanical functions in a printer. Most laser printers have two or three gearboxes that can be replaced individually if one fails

eSATA

Serial ATA-based connector for external hard drives and optical drives.

COM ports

Serial communications ports once common on computers. COMx is used to designate a uniquely numbered COM port such as COM1, COM2, etc.

PCIe (PCI Express)

Serialized successor to PCI and AGP that uses the concept of individual data paths called lanes. May use any number of lanes, although a single lane (x1) and 16 lanes (x16) are the most common on motherboards.

SATA (serial ATA)

Serialized version of the ATA standard that offers many advantages over PATA (parallel ATA) technology, including thinner cabling, keyed connectors, and lower power requirements.

beep codes

Series of audible tones produced by a motherboard during the POST. These tones identify whether the POST has completed successfully or whether some piece of system hardware is not working properly. Consult the manual for your particular motherboard for a specific list of beep codes.

front-view projector

Shoots the image out the front and counts on you to put a screen in front at the proper distance.

patch cables

Short (2 to 5 foot) UTP cables that connect patch panels to the hubs.

MP3

Short for MPEG Audio Layer 3, a type of compression used specifically for turning high-quality digital audio files into much smaller, yet similar-sounding, files.

worm

Similar to a virus, except it does not need to attach itself to other programs to replicate. It can replicate on its own through networks, or even hardware like Thunderbolt accessories

duplexing

Similar to mirroring in that data is written to and read from two physical drives, for fault tolerance. Separate controllers are used for each drive, both for additional fault tolerance and for additional speed. Considered RAID level 1. Also called disk duplexing or drive duplexing.

brute force

Simple attack that attempts to guess credentials or identify vulnerabilities by trying many possibilities

Settings app

Since its introduction in Windows 8, it has grown to combine a huge number of otherwise disparate utilities, apps, and tools traditionally spread out all over your computer into one fairly unified, handy Windows app

HDMI (High-Definition Multimedia Interface)

Single multimedia connection that includes both high-definition video and audio. Used to connect a computer to LCDs, projectors, and VR headsets

bit

Single binary digit. Also, any device that can be in an on or off state.

clock cycle

Single charge to the clock wire (CLK) of a CPU, informing the CPU that another piece of information is waiting to be processed

MFD (multifunction device)

Single device that consolidates functions from more than one document-handling device, such as a printer, copier, scanner, or fax amchine

software

Single group of programs designed to do a particular job; always stored on mass storage devices

laser

Single-wavelength, in-phase light source that is sometimes strapped to the head of sharks by bad guys. Note to henchmen: Lasers should never be used with sea bass, no matter how ill-tempered they might be.

throw

Size of the image a projector displays at a certain distance from the screen. Alternately, what you do with a computer that you just can't seem to get working.

ID badge

Small card or document for confirming the identify of its holder and what access they should be granted. May use built-in authentication tools such as RFID or smart card to function as "something you have" authentication factor

module

Small circuit board that DRAM chips are attached to. Also known as a "stick.

mini-DIN

Small connection most commonly used for keyboards and mice. Many modern systems implement USB in place of mini-DIN connections. Also called PS/2.

wireless locator

Small device with signal lights to indicate the presence of Wi-Fi signals

traces

Small electrical connections embedded in a circuit board.

power supply fan

Small fan located in a system power supply that draws warm air from inside the power supply and exhausts it to the outside.

recovery partition

Small hidden partition on a system's primary hard drive with a factory-fresh OS image to recover and reinstall from

icon

Small image or graphic, most commonly found on a system's desktop, that launches a program when selected

Standoffs

Small mechanical separators that screw into a computer case. A motherboard is then placed on top of the standoffs, and small screws are used to secure it to the standoffs.

context menu

Small menu brought up by right-clicking on objects in Windows

texture

Small picture that is tiled over and over again on walls, floors, and other surfaces to create the 3-D world

patch

Small piece of software released by a software manufacturer to correct a flaw or problem with a particular piece of software. also called an update

connector

Small receptacle used to attach a cable to a device or system common types of connector include USB, PS/2, RJ-45, VGA, HDMI, DVI, HD15, DisplayPort, and thunderbolt

mantrap

Small room with a set of doors; one to the unsecured area and one to a secured area. Only one door can open at a time, and individuals must authenticate to continue. Combats tailgating.

Liquid Contact Indicator (LCI)

Small sticker that permanently changes color after getting wet, often from white to red. Installed at various locations inside mobile and portable devices.

mobile device

Small, highly portable computing devices with tightly integrated components designed to be worn or carried by the user. Includes smartphones, tablets, and wearable devices

Mini-USB

Smaller USB connector often found on digital cameras.

thread

Smallest logical division of a single program.

Android

Smartphone and table OS created by Google

mobile payment service

Smartphone feature that can use a connected bank account to automatically transfer payments to merchants. May work in conjunction with Near Field Communication (NFC)

Disk Management

Snap-in available with the Microsoft Management Console that enables techs to configure the various disks installed in a system; available in Computer Management in Administrative Tool.

telephone scams

Social engineering attack in which the attacker makes a phone call to someone in an organization to gain information.

ZIF (zero insertion force) socket

Socket for CPUs that enables insertion of a chip without the need to apply pressure. Intel promoted this socket with its overdrive upgrades. The chip drops effortlessly into the socket's holes, and a small lever locks it in.

antivirus program

Software designed to combat viruses either by seeking out and destroying them or passively guarding against them.

anti-malware program

Software designed to identify and block or remove malware. Typically powered by frequently updated definition files containing the signatures of known malware

Closed source software

Software for which the source code is kept secret

open source software

Software for which the source code is published instead of kept secret. Typically released under an open source license that specifies terms for those who wish to use the software or modify its source

virtual NIC

Software network interface for a virtual machine. For access to a broader network than the host system is connected to, the virtual NIC needs to be bridged to the host's physical NIC. This enables the virtual NIC to receive an address from DHCP, just like a physical NIC

emulator

Software or hardware that converts the commands to and from the host machine into an entirely different platform.

terminal emulation

Software that enables a computer to communicate with another computer or network as if the computer were a specific type of hardware terminal.

hypervisor

Software that enables a single computer to run multiple operating systems simultaneously

proxy server

Software that handles multiple connections to the Internet to go through one protected computer. Common security feature in the corporate world. Applications that want to access Internet resources send requests to the proxy server instead of trying to access the Internet directly, which both protects the client computers and enables the network administrator to monitor and restrict Internet access

freeware

Software that is distributed for free, with no license fee.

virtual printer

Software that presents itself as a printer, but does something else rather than just print the document, such as saving it to a given file type

spyware

Software that runs in the background of a user's PC, sending information about browsing habits back to the company that installed it onto the system

network protocol

Software that takes the incoming data received by the network card, keeps it organized, sends it to the application that needs it, and then takes outgoing data from the application and hands it to the NIC to be sent out over the network.

SDK (software development kit)

Software that used to create custom applications or add features to existing applications on a mobile device.

DUN (Dial-up Networking)

Software used by Windows to govern the connection between the modem and the ISP.

keylogger

Software, usually malware, that copies, saves, and sometimes uploads all keystrokes and other inputs on a computer. Keyloggers are used gather information such as passwords, sites visited, and other activities performed on a computer

LED (light-emitting diode)

Solid-state device that vibrates at luminous frequencies when current is applied.

PC tech

Someone with computer skills who works on computers.

PCM (pulse code modulation)

Sound format developed in the 1960s to carry telephone calls over the first digital lines.

Plenum

Space in the ceiling, walls, and floor where special plenum-grade (fire-retardant) network cables can be run out of sight

5.1 Speaker system

Speaker setup consisting of four satellite speakers plus a center speaker and a subwoofer

7.1 Speaker system

Speaker setup consisting of six satellite speakers (two front, two side, two rear) plus a center speaker and a subwoofer

2.1 Speaker system

Speaker setup consisting of two stereo speakers combined with a subwoofer

Ownership permission

Special NTFS permissions granted to the account that owns a file or folder. Owners can do anything they want to the files and folders they own, including changing their permissions.

riser card

Special adapter card, usually inserted into a special slot on a motherboard, that changes the orientation of expansion cards relative to the motherboard. Riser cards are used extensively in slimline computers to keep total depth and height of the system to a minimum. Sometimes called a daughterboard.

cache (disk)

Special area of RAM that stores the data most frequently accessed from the hard drive. Cache memory can optimize the use of your systems.

anti static wrist strap

Special device worn around the wrist with a grounding connection designed to equalize electrical potential between a technician and an electronic device. Used to prevent electrostatic discharge.

dynamic disks

Special feature of Windows that enables users to span a single volume across two or more drives. Dynamic disks do not have partitions; they have volumes. Dynamic disks can be striped, mirrored, and striped or mirrored with parity.

CDDA (CD-Digital Audio)

Special format used for early CD-ROMs and all audio CDs; divides data into variable-length tracks. A good format to use for audio tracks but terrible for data because of lack of error checking.

thermal paper

Special heat-sensitive paper for use in thermal printers

function (Fn) key

Special key on many laptops that enables some keys to perform a third duty.

swap partition

Special partition found on Linux and UNIX systems that behaves like RAM when your system needs more RAM than is installed

Take Ownership

Special permission allowing users to seize control of a file or folder and potentially prevent others from accessing the file/folder.

power saving modes

Special power modes that limit or modify device functionality in order to prolong battery life. May take steps such as disabling communications, reducing processor speed, limiting programs, and dimming the screen

cache (L1, L2, L3, etc.)

Special section of fast memory, usually built into the CPU, used by the onboard logic to store information most frequently accessed by the CPU.

ECC (error-correcting code)

Special software, embedded on hard drives, that constantly scans the drives for bad blocks

Anti static mat

Special surface on which to lay electronics. These mats come with a grounding connection designed to equalize electrical potential between a workbench and one or more electronic devices. Used to prevent electrostatic discharge

loopback test

Special test to confirm a NIC can send and receive data. A full external loopback test requires a loopback plug inserted into the NIC's port

DVI (Digital Visual Interface)

Special video connector designed for digital to- digital connections; most commonly seen on PC video cards and LCD monitors. Some versions also support analog signals with a special adapter.

troubleshooting methodology

Steps a technician uses to solve a problem. CompTIA A_ defines six steps: identify the problem, establish a theory of probable cause (question the obvious); test the theory to determine cause; establish a plan of action to resolve the problem and implement a solution; verify full system functionality and, if applicable, implement preventative measures, and document findings, actions, and outcomes

parity space

Storage Space that adds resiliency similar to RAID 5 or RAID 6

simple space

Storage Space that just pools storage space, like JBOD

register

Storage area inside the CPU used by the onboard logic to perform calculations. CPUs have many registers to perform different functions.

Magnetic hard drives

Storage devices that read and write data encoded magnetically onto spinning aluminum platters

hybrid hard drive (HHD)

Storage drive that combines the flash memory used in solid-state drives with the spinning platters used in magnetic hard drives; a compromise between the speed and power efficiency of SSDs and the capacity of HDDs

EFS (Encrypting File System)

Storage organization and management service, such as NTFS, that has the capability of applying a cipher process to the stored data.

mirror space

Storage space that mirrors files across two or more drives, like RAID 1 or RAID 10

untrusted source

Stores and sites where apps can be obtained outside of the legitimate trusted sources run by major vendors

partition boot sector

Stores information for booting from the partition, such as the location of OS boot files

Chromebook

Strictly, any portable computer running Google's Chrome OS. Chromebooks offer an experience focused on Web applications by making use of virtually unlimited data storage in the cloud and software as a service (SaaS) applications available over the Web. Because they offload so much work, Chromebooks have a reputation for being cheap and light, but premium Chromebooks are increasingly common.

cat 7

Supports 10-Gbps networks at 100-meter segments; shielding for individual wire pairs reduces crosstalk and noise problems. CAT 7 is not a ANSI/EIA standard.

interrupt/interruption

Suspension of a process, such as the execution of a computer program, caused by an event external to the computer and performed in such a way that the process can be resumed. Events of this kind include sensors monitoring laboratory equipment or a user pressing an interrupt key

object

System component that is given a set of characteristics and can be managed by the operating system as a single entity

environment variables

System data such as the date and time, currently logged-in users, running operating system version, and more. Scripts and programs on a system often use these variables to tailor their behavior to the system's capabilities and configuration

WWW (World Wide Web)

System of Internet servers that supports documents formatted in HTML and related protocols. Can be accessed by applications that use HTTP and HTTPS, such as Web browsers.

data classification

System of organizing data according to its sensitivity. Common classifications include public, highly confidential, and top secret.

DLP (Data Loss Prevention)

System or set of rules designed to stop leakage of sensitive information. Usually applied to Internet appliances to monitor outgoing network traffic.

DNS (Domain Name System)

TCP/IP name resolution system that translates a host name into an IP address. Uses UDP port 53

Startup

Tab added to Task Manager in Windows 8 that allows a user to control which programs start with Windows and see what impact they are having on load time

Details

Tab added to Task Manager in Windows 8 to collect much of the detail from the older Processes tab, including executable names, PIDs, status, executing user, a description, and present resource use. Many more columns can be enabled as well

Processes

Tab in Task Manager that lists all running processes on a system. Frequently a handy tool for ending buggy or unresponsive processes

applications

Tab in Task Manager that lists running applications

Users

Tab in Task Manager that shows other logged in users and enables you to log off other users if you have the proper permissions. Starting in Windows 8, also includes information on resources consumed by programs the user is running

Performance

Tab in Task Manager that tracks PC performance, including CPU usage, available physical memory, size of the disk cache, and other details about memory and processes

System Protection

Tab in Windows System Properties dialog box that enables you to configure how and when the system will create restore points and provides easy access to existing restore points via System Restore

Services

Tab in Windows Task Manager that lists all running services on a system

partition table

Table located in the boot sector of a hard drive that lists every partition on the disk that contains a valid operating system.

drive cloning

Taking a PC and making a duplicate of the hard drive, including all data, software, and configuration files, and transferring it to another PC. see image deployment

memory addressing

Taking memory address from system RAM and using it to address non-system RAM or ROM so the CPU can access it

Networking

Task Manager tab in Windows 7 (merged into the Performance tab in Windows 8) which shows activity on current network connections

Mobile Device Management (MDM) Policies

Technical controls that govern how mobile devices are used as tools in the workplace. See MDM

lithium polymer (LiPo)

Technically, a variant of Li-Ion batteries that use a solid, polymer electrolyte. In practice, this term is commonly applied to traditional Li-Ion batteries packed in polymer bags.

DMA (Direct Memory Access)

Technique that some PC hardware devices use to transfer data to and from the memory without using the CPU

Scalable Link Interface (SLI)

Technology for connecting two or more NVIDIA GPUs together in a system. AMD competes with CrossFire technology

NX bit

Technology that enables the CPU to protect certain sections of memory. This feature, coupled with implementation by the operating system, stops malicious attacks from getting to essential operating system files. Microsoft calls the feature Data Execution Prevention (DEP) turned on by default in every OS

face lock

Technology that enables use of facial features to unlock a mobile device or personal computer.

Power over Ethernet (PoE)

Technology that provides power and data transmission through a single network cable.

REt (Resolution Enhancement technology)

Technology that uses small dots to smooth out jagged edges that are typical of printers without RET, producing a higher-quality print job.

proprietary

Technology unique to a particular vendor.

S/MIME (Secure/Multipurpose Internet Mail Extensions)

Technology used to configure digital signature settings for e-mail and contacts from a corporate address book, depending on how the corporate e-mail server is set up

Telnet

Terminal emulation program for TCP/IP networks that allows one machine to control another as if the user were sitting in front of it. Uses port 23.

SSH (Secure Shell)

Terminal emulation program similar to Telnet, except that the entire connection is encrypted. Uses port 22.

force stop

Terminate an Android app and all associated background processes. More extreme than simply closing the app, which may leave background processes running.

Command Prompt

Text prompt for entering commands

Command Line Interface (CLI)

Text user interface. Users input text commands and receive text output. CLI commands, which are flexible and often faster (or use fewer resources) than a graphical equivalent, are also easy to compose into scripts for performing frequent tasks

ANSI/TIA

The Telecommunication Industry Association (TIA) establishes the UTP categories under the ANSI/TIA 568 specification. The AMerican National Strandards Institute (ANSI) accredits TIA standards to ensure compatibility of industry and international standards see also UTP

Aero

The Windows 7 desktop environment. often used as a shorthand for one of its more obvious aesthetic effects: a window transparency feature called Aero Glass

remotely wipe

The ability to remotely delete user data from a mobile device that has been lost or stolen

Phising

The act of trying to get people to give their user names, passwords, or other security information by pretending to be someone else electronically

tethering

The act of using a cellular-network-connected mobile device as a mobile hotspot.

host ID

The address of a TCP/IP device such as a computer, printer, camera, or other device

potential

The amount of electrical energy stored in an object

lumens

The amount of light given off by a light source from a certain angle that is perceived by the human eye. Unit of measure for amount of brightness on a projector or other light source.

impedance

The amount of resistance to an electrical signal on a wire. Relative measure of the amount of data a cable can handle.

response rate

The amount of time it takes for all the sub-pixels on an LCD panel to change from one state to another. This change is measured in one of two ways: black to white (BtW) measures how long it takes the pixels to go from pure black to pure white and back again, and gray to gray (GTG) measures how long it takes the pixels to go from one gray state to another

tiles

The building blocks of Windows 8's Modern UI, as potentially "smart" app shortcuts, capable of displaying dynamic and changing information without even open- ing the app.

segment

The connection between a computer and a switch

working directory

The current directory used by command-line commands unless they explicitly specify a target file or directory. The prompt usually indicates the working directory

home screen

The default "desktop" of a mobile device.

soft reset

The equivalent of a reboot or restart for a mobile device. An important troubleshooting step because it clears running programs from memory and restarts the operating system. Some portable devices that closely resemble mobile devices may also use soft resets

5G

The fifth generation of cellular data technologies. Technologies in the wave are still cutting their teeth, with development underway in 2019

Comptia A+ 220-1001

The first half of the CompTIA A+ certification for computer technicians. The 1001 exam focuses primarly on understanding terminology and technology, how to do fundamental tasks such as upgrading RAM and basic network and mobile device support

processing (printing)

The first step of the laser printing process, in which the printer translates incoming print commands into pages rendered for printing

ExpressCard

The high-performance serial version of the PC Card that replaced PC Card slots on laptop PCs over the past decade. ExpressCard comes in two widths: 34 mm and 54 mm, called ExpressCard/34 and ExpressCard/54.

Windows Preinstallation Environment (Windows PE)

The installation program for Windows

Mini-ITX

The largest and the most popular of the three ITX form factors. At a miniscule 6.7 by 6.7 inches, Mini-ITX competes with microATX and proprietary small form factor (SFF) motherboards.

kernel panic

The linux equivalent of Blue screen of death (BSOD). An error from which the OS can't recover without a reboot. See BSoD

Charms bar

The location in Windows 8 and 8.1 of the charms tools. Accessed by moving the cursor to the upper-right corner of the screen.

clock speed

The maximum number of clock cycles that a CPU can handle in a given period of time. Measured in MHz or GHz. In modern CPUs, the internal speed is a multiple of the external speed. see also Clock-multiplying CPU.

Mini Secure Digital (MiniSD)

The medium-sized form factor of the SD flash memory standard.

mv

The move command in Linux and Mac OS X.

CompactFlash (CF)

The oldest, most complex and physically largest of all removable flash media cards

ios

The operating system of Apple mobile devices such as smartphones and tablets

RAID 10

The opposite of RAID 0+1, two mirrored RAID 0 configurations. Provides both speed and redundancy, and also requires four disks

Metro UI

The original name for the Windows 8 user interface. Due to legal concerns, it was rebranded the "Modern UI"

%SystemRoot%

The path where the operating system is installed.

color space

The portion of all possible colors that a device (such as an LCD display or camera) is able to display or save

touch interface

The primary user interface on modern mobile devices where keys are replaced with tactile interaction.

backup testing

The process of ensuring that file or system backups have produced backups from which you can restore usable systems and files

authentication

The process of identifying and granting access to some user trying to access a system

sync

The process of keeping files on mobile devices up to date with the versions on desktop computers or over the Internet via cloud-based services

patch management

The process of keeping software updated in a safe and timely fashion

formatting

The process of preparing a partition to store files by creating a file system to organize the blocks and creating a root directory

salting

The process of protecting password hashes from being easily reversed with a rainbow table by adding additional values to each password before hashing and storing it

ISDN (integrated services digital network)

The process of sending telephone transmission across fully digital lines end-to-end, replacing the analog telephone system. ISDN is superiorto POTS telephone lines because it supports a transfer rate of up to 128 Kbps for sending information from computer to computer. It also allows data and voice to share a common phone line. DSL reduced demand for ISDN substantially.

authorization

The process that defines what resources an authenticated user may access and what he or she may do with those resources.

CompTIA A+ 220-1002

The second half of the CompTIA A+ certification for computer technicians. The 1002 exam focuses primarly on software, security, and troubleshooting

processing (computing)

The second step of the computing process, where the CPU completes the tasks that the user's input has given it

Micro Secure Digital (MicroSD)

The smallest form factor of the SD flash memory standard. Often used in mobile devices.

CRT (cathode ray tube)

The tube of a monitor in which rays of electrons are beamed onto a phosphorescent screen to produce images. Also a shorthand way to describe a monitor that uses CRT rather than LCD technology.

U (units)

The unique height measurement used with equipment racks; 1 U equals 1.75 inches. A 1U device fits in a 1.75-inch space, a 2U fits in a 3.5-inch space, and a 4U device fits in a 7-inch space

topology

The way computers connect to each other in a network.

transfer corona

Thin wire, usually protected by other thin wires, that applies a positive charge to the paper during the laser printing process, drawing the negatively charged toner particles off of the drum and onto the paper. Newer printers accomplish the same feat using a transfer roller that draws the toner onto the paper.

Ultrabook

Thin, powerful laptop powered by Intel processors and built according to the Intel design specification. Competes directly with the Apple Mac Air.

Level 3 (L3) cache

Third RAM cache accessed by the CPU. Much larger and slower than the L1 and L2 caches, and accessed only if the requested program/data is not in the L2 cache.

net user

This subcommand of the Windows net command enables a user to create, delete, and change user accounts

refresh rate

Time required for a monitor to redraw the whole screen

MBR (Master Boot Record)

Tiny bit of code that takes control of the boot process from the system BIOS.

shunt

Tiny connector of metal enclosed in plastic that creates an electrical connection between two posts of a jumper

sub-pixels

Tiny liquid crystal molecules arranged in rows and columns between polarizing filters used in LCDs.

debug

To detect, trace, and eliminate errors in computer programs.

dumpster diving

To go through someone's trash in search of information.

boot

To initiate an automatic routine that clears the memory, loads the operating system, and prepares the computer for use. Term is derived from "pull yourself up by your bootstraps." Computers must do that because RAM doesn't retain program instructions when power is turned off. A cold boot occurs when the PC is physically switched on. A warm boot loads a fresh OS without turning off the computer, lessening the strain on the electronic circuitry. To do a warm boot, press the ctrl-alt-delete keys twice in rapid succession (the three-fingered salute).

cluster

To overcome some limitations in addressing inherent in each file system, Windows file systems organize data into groups called clusters. Cluster size varies by file system and partition size

identify the problem

To question the user and find out what has been changed recently or is no longer working properly. Step 1 of 6 in the CompTIA troubleshooting theory

overclocking

To run a CPU or video processor faster than its rated speed.

Local Users and Groups

Tool enabling creation and changing of group memberships and accounts for users.

Performance Options

Tool enabling users to configure CPU, RAM, and virtual memory settings.

Display applet

Tool in Windows 7/8/8.1 used to adjust display settings, including resolution, refresh rate, driver information, and color depth

shell

Tool that interprets command-line input, also known as the command-line interpreter

NetBoot

Tool that makes it easy to install, upgrade, and manage OS X on many remote systems at once, over a network

tech toolkit

Tools a PC tech should never be without, including a Phillips-head screwdriver, a pair of tweezers, a flat-head screwdriver, a hemostat, a Torx wrench, a parts retriever, and a nut driver or two.

address space

Total amount of memory addresses than an address bus can contain

bank

Total number of DIMMs that can be accessed simultaneously by the chip set. The "width" of the external data bus divided by the "width" of the DIMM sticks. Specific DIMM slots must be populated to activate dual-, triple-, or quad-channel memory

tap

Touchscreen gesture where you press a spot on the screen to start an app or interact with a running app.

laptop

Traditional clamshell portable computing device with built-in LCD monitor, keyboard, and trackpad.

half-duplex

Transmission mode where a device can either send or receive, but not do both at once

stripe set

Two or more drives in a group that are used for a striped volume.

satellites

Two or more standard stereo speakers to be combined with a subwoofer for a speaker system (i.e., 2.1, 5.1, 7.1, etc.).

file extension

Two, three, four, five, or more letters that follow a filename and identify the type of file (file format). Common file extensions are .zip, .exe, .doc, .java, and .xhtml

DDR SDRAM (double data rate SDRAM)

Type of DRAM that makes two processes for every clock cycle. (See also DRAM.)

TFT (thin film transistor)

Type of LCD screen. (See also active matrix.)

DDR4 SDRAM

Type of SDRAM that offers higher density and lower voltages than DDR3, and can handle faster data transfer rates. Maximum theoretical capacity of DDR4 DIMMs is up to 512 GB.

DDR2 SDRAM

Type of SDRAM that sends 4 bits of data in every clock cycle. (See also DDR SDRAM.)

DDR3 SDRAM

Type of SDRAM that transfers data at twice the rate of DDR2 SDRAM.

fingerprint lock

Type of biometric device that enables a user to unlock a mobile device using a fingerprint.

dictionary attack

Type of brute force attack using a dictionary to guess things like usernames and passwords. Don't think Webster's- these dictionaries may be full of usernames and passwords that have leaked or been used as defaults over the years

disk duplexing

Type of disk mirroring using two separate controllers rather than one; faster than traditional mirroring because one controller does not write each piece of data twice.

LCD (liquid crystal display)

Type of display commonly used on portable computers. LCDs have also replaced CRTs as the display of choice for desktop computer users. LCDs use liquid crystals and electricity to produce images on the screen.

DC (direct current)

Type of electricity in which the flow of electrons is in a complete circle in one direction

multimode

Type of fiber optic cabling capable of transmitting multiple light signals at the same time using different reflection angles within the cable core. Signals tend to degrade over distance, limiting multimode cable to short distances

single-mode fiber optic cabling

Type of fiber optic cabling that uses laser light to transmit at very high rates over long distances. Still fairly rare

LC

Type of fiber optic connector

active matrix

Type of liquid crystal display (LCD) that replaced the passive matrix technology used in most portable computer displays. Also called TFT (thin film transistor)

adware

Type of malicious program that downloads ads to a user's computer, generating undesirable network traffic

extended partition

Type of nonbootable hard disk partition. May only have one extended partition per disk. Purpose is to divide a large disk into smaller partitions, each with a separate drive letter.

dual-voltage

Type of power supply that works with either 110- or 220-volt outlets.

M.2

Type of space-efficient expansion slot common in recent portable computers. Formerly known as Next Generation Form Factor (NGFF). Also found on some desktop motherboards. While M.2 is a general expansion slot supporting devices such as WI-Fi cards, it's often used to install an NVMe SSD

optical disc/media

Types of data discs (such as DVDs, CDs, BDs, etc.) that are read by a laser.

Tv tuner

Typically an add-on device that allows users to watch television on a computer.

Secure Boot

UEFI feature that secures the boot process by requiring properly signed software. This includes boot software and software that supports specific, essential components.

ls

UNIX equivalent of the dir command, which displays the contents of a directory

micro-USB

USB connector commonly found on Android phones. Slowly being replaced by USB type-C connectors (especially in Android phones)

Low-Speed USB

USB standard that runs at 1.5 Mbps. Also called USB 1.1.

Full-Speed USB

USB standard that runs at 12 Mbps. Also known as USB 1.1.

Hi-Speed USB

USB standard that runs at 480 Mbps. Also referred to as USB 2.0.

RJ (registered jack) connector

UTP cable connector, used for both telephone and network connections. RJ-11 is a connector for four-wire UTP; usually found in telephone connections. RJ-45 is a connector for eight-wire UTP; usually found in network connections.

BNC

Uncommon coax connector secured with a quarter twist

electrostatic discharge (ESD)

Uncontrolled rush of electrons from one object to another. A real menace to PCs, as it can cause permanent damage to semiconductors.

MAC (media access control) address

Unique 48-bit address assigned to each network card. IEEE assigns blocks of possible addresses to various NIC manufacturers to help ensure that the address is always unique. The Data Link layer of the OSI model uses MAC addresses to locate machines.

scan code

Unique code corresponding to each key on the keyboard, sent from the keyboard controller to the CPU.

SID (security identifier)

Unique identifier for every PC that most techs change when cloning

SCSI ID

Unique identifier used by SCSI devices. No two SCSI devices may have the same SCSI ID.

Stateful Packet Inspection (SPI)

Used by hardware firewalls to inspect each incoming packet individually for purposes such as blocking traffic that isn't in response to outgoing requests

channel

Used in a common method for numbering boot devices; the first boot device is channel 1, the second is channel 2, etc.

vertices

Used in the second generation of 3-D rendering; have a defined X, Y, and Z position in a 3-D world.

counter

Used to track data about a particular object when using Performance Monitor

power good wire

Used to wake up the CPU after the power supply has tested for proper voltage.

standard user account

User account in Windows that has limited access to a system. Accounts of this type cannot alter system files, cannot install new programs, and cannot edit some settings by using the Control Panel without supplying an administrator passwords.

administrator account

User account, created when the OS is first installed, that is allowed complete, unfettered access to the system without restriction

Guests group

User group that enables someone without an account to use a system. see group

effective permissions

User's combined permissions granted by multiple groups.

Desktop

User's primary interface to the Windows operating system.

Default user accounts and groups

Users or groups that are enabled by default. Some, such as the guest account, represent a security risk

Ethernet over power

Uses a building's existing electrical network for Ethernet. Requires specialized bridges between the Ethernet network and power outlets

Raid 5

Uses block-level and parity data striping. Requires three or more drives.

RAID 0

Uses byte-level striping and provides no fault tolerance.

inkjet printer

Uses liquid ink, sprayed through a series of tiny jets, to print text or images on a piece of paper. (which is typically fed into the printer from a paper tray under the printer, or an angled feeder on the back of the printer

Raid 1

Uses mirroring or duplexing for increased data redundancy.

impact printer

Uses pins and inked ribbons to print text or images on a piece of paper. Impact printers can make use of a few special types of paper. Tractor-feed paper has holes so that printers with sprockets can continuously print massive stacks of the stuff. Special multi-part impact paper can be used to print receipts in duplicate, triplicate, or more

client-side virtualization

Using a hypervisor installed on a client machine to run a virtual machine. The VM may be created and stored on the client machine or accessed over the netwrok

Augmented Reality (AR)

Using some form of hardware (such as a smartphone or an AR headset) to enhance the wearer's experience of the world by adding an interface layer. The interface layer presents information such as the time or navigation instructions and may also support interaction

multicore processing

Using two or more execution cores on one CPU die to divide up work independently of the OS.

dual-channel architecture

Using two sticks of RAM (either RDRAM or DDR) to increase throughput. See also triple-channel architecture and quad-channel architecture

buffered/registered RAM

Usually seen in motherboards supporting more than four sticks of RAM; used to address interference issues caused by the additional sticks. It accomplishes this with a small register installed on some memory modules to act as a buffer between the DIMM and the memory controller

snap-ins

Utilities that can be used with the Microsoft Management Console

Disk Cleanup

Utility built into Windows that can help users clean up their disks by removing temporary Internet files, deleting unused program files, and more.

System Restore

Utility in Windows that enables you to return your PC to a recent working configuration when something goes wrong. System Restore enables you to select a restore point and then returns the computer's system settings to the way they were at that restore point—all without affecting your personal files or e-mail.

Event Viewer

Utility made available in Windows as an MMC snap-in that enables users to monitor and audit various system events, including network bandwidth usage and CPU utilitzation

Device Manager

Utility that enables techs to examine and configure all the hardware and drivers in a Windows PC.

motherboard book

Valuable resource when installing a new motherboard. Normally lists all the specifications about a motherboard, including the type of memory and type of CPU usable with the motherboard.

checksum

Value generated from some data, like a file, and saved for comparing to other checksums later. Can be used to identify identical data, such as files on a user's system that match known viruses. Checksums can also be used to monitor whether a program is changing itself over time, which is a strong warning sign that it may be malware that evolves to avoid detection

subnet mask

Value used in TCP/IP settings to divide the IP addess of a host into its component parts: network ID and host ID

nit

Value used to measure the brightness of an LCD display. A typical LCD display has a brightness of between 100 and 400 nits.

attributes

Values in a file that determine the hidden, read-only, system, and archive status of the file.

gaming laptop

Variant of the desktop-replacement laptop designed to play resource-hungry games on the go, often at a high price

microATX (uATX)

Variation of the ATX form factor, which uses the ATX power supply. MicroATX motherboards are generally smaller than their ATX counterparts but retain all the same functionality.

SATA Express (SATAe)

Version of SATA that ties capable drives directly into the PCI Express bus on the motherboards. Each lane of PCIe 3.0 is capable of handling up to 8 Gbps of data throughput. A SATAe drive grabbing two lanes, therefore, could move a whopping 16 Gbps through the bus

Windows XP

Version of Windows that replaced both the entire Windows 9x line and Windows 2000; does not have a Server version. No longer supported by Microsoft.. succeeded by windows vista

CRC (Cyclic Redundancy Check)

Very accurate mathematical method used to check for errors in long streams of transmitted data. Before data is sent, the main computer uses the data to calculate a CRC value from the data's contents. If the receiver calculates from the received data a different CRC value, the data was corrupted during transmission and is re-sent. Ethernet packets use the CRC algorithm in the FCS portion of the frame.

SRAM (Static RAM)

Very high-speed RAM built into CPUs that reduces wait states by preloading as many instructions as possible and keeping copies of already run instructions and data in case the CPU needs to work on them again

guest account

Very limited built-in account type for Windows; a member of the Guest group.

audio jack

Very popular connector used to transmit two audio signals; perfect for stereo sound. Confusingly, you can find the diameter described as both 1/8 inch and 3.5 mm

SD (Secure Digital)

Very popular format for flash media cards; also supports I/O devices. In addition to full-sized SD cards, the format also includes two smaller form factors: miniSD and microSD

xD (Extreme Digital) picture card

Very small flash media card format.

interpolation

Video capture and display technology that calculates the color value and light intensity between pixels to fill in information that is not directly captured or saved

XGA (extended graphics array)

Video display mode of 1024 × 768.

SXGA

Video display mode of 1280 × 1024.

WYXGA

Video display mode of 1920 x 1200

SVGA (super video graphics array)

Video display mode of 800 × 600. Native displays are rare these days, but Windows might go into SVGA mode if the video driver is corrupt

WXGA

Video display mode. Most often of 1366 x 768, though a variety of similar resolutions are also known as WXGA

3-D graphics

Video technology that attempts to create images with the same depth and texture as objects seen in the real world

high dynamic range (HDR)

Video technology that increases the bandwidth of display colors and light intensity above standard dynamic range

snapshot

Virtualization feature that enables you to save an extra copy of the virtual machine as it is exactly at the moment the snapshot is taken.

polymorphic virus

Virus that attempts to change its signature to prevent detection by antivirus programs, usually by continually scrambling a bit of useless code. Often shortened to polymorph

stealth virus

Virus that uses various methods to hide from antivirus software

user interface

Visual representation of the computer on the monitor that makes sense to the people using the computer, through which the user can interact with the computer. This can be a graphical user interface (GUI) like windows 10 or a command-line interface like Windows Powershell

virtual assistant

Voice-activated technology that responds to user requests for information. Virtual assistants can be used to search the Internet, make reminders, do calculations, and launch apps.

simple volume

Volume created when setting up dynamic disks. Acts like a primary partition on a dynamic disk.

mirrored volume

Volume that is mirrored on another volume. (See also mirroring.)

spanned volume

Volume that uses space on multiple dynamic disks

respect

What all techs should show their customers

roaming

When a mobile device connects to a network not owned by its home carrier

parallel execution

When a multicore CPU processes more than one thread.

replication

When a virus makes copies of itself, often by injecting itself into other executables

viewing angle

Width (measured from the center to the side of a display) range within which the image can be fully seen

Start Screen

Windows 10 version of the start menu, which functions as a combination of the traditional Start menu and the Windows 8/8.1 Modern UI

Windows Explorer

Windows 7 - utility that enables you to manipulate files and folders stored on the drives in your computer. Rebranded File Explorer in Windows 8, 8.1, and 10

System Tools

Windows 7 menu containing tools such as System Information and Disk Defragmenter, accessed by selecting Start | All Programs | Accessories | System Tools

Advanced Startup Options menu

Windows 7 menu that can be reached during the boot process that offers advanced OS startup options, such as to boot to Safe Mode or boot into Last Known Good Configuration

Task Scheduler

Windows 7 utility enabling users to set tasks to run automatically at certain times

Backup and Restore

Windows 7's backup utility. It offers two options: create a backup or restore from a backup. Windows 10 still supports restoring these backups, which it calls Backup and Restore (Windows 7) see also File History

navigation pane

Windows 7's name for the Folders list in Windows Explorer.

Windows Easy Transfer

Windows 7/8/8.1 method of transferring user data and personalization settings to a new PC. It is not available in Windows 10

bootmgr

Windows Boot manager. Manages the boot process using information from the Boot Configuration Data (BCD) file

Power Options

Windows Control Panel applet that enables better control over power use by customizing a Balanced, Power saver, or High-performance power plan

Sync Center

Windows Control Panel applet where network files marked as Always available offline may be viewed

Programs and Features

Windows Control Panel applet; enables uninstalling or changing program options and altering Windows features.

Reset your PC

Windows RE option in Windows 8 and later that nukes the system— deleting all apps, programs, user files, and user settings—and presents a fresh installation of Windows. Use Reset as the last resort when troubleshooting a PC. And back up data first, if possible. Renamed to Remove everything in Windows 10

Remove everything

Windows Recovery Environment option in Windows 10 that deletes all apps, programs, user files, and user settings - resulting in a fresh installation of Windows. Use as a last resort when troubleshooting (and back up data first)

keep my files

Windows Recovery Environment option in Windows 10 that rebuilds the OS, but preserves user files, settings and Microsoft Store applications (while deleting all other applications on the system)

Refresh your PC

Windows Recovery Environment option in Windows 8/8.1 that rebuilds the OS, but preserves all user files and settings and any applications purchased from the Windows Store. Note well: Refresh deletes every other application on a system. Renamed Keep my files in Windows 10

shutdown

Windows and Linux command for shutting down the computer

hostname

Windows command for displaying the name of a computer

gpresult

Windows command for listing group policies applied to a user.

gpupdate

Windows command for making immediate group policy changes in an individual system.

taskkill

Windows command-line tool for killing running processes

tasklist

Windows command-line tool for listing and managing processes

tracert

Windows command-line utility used to follow the path a packet takes between two hosts. Called traceroute in Mac OS X and Linux.

ReadyBoost

Windows feature enabling the use of flash media (USB/memory cards) as dedicated virtual memory.

UAC (User Account Control)

Windows feature implemented to stop unauthorized changes to Windows. UAC enables stanard accounts to do common tasks and provides a permissions dialog box when standard and administrator accounts do certain things that could potentially harm the computer (such as attempt to install a program)

offline files

Windows feature the enables storing a local, duplicate copy of files and folders on a hard drive. When the laptop connects to a network, Windows automatically syncs those offline files with the files and folders on a file server or other PC

Documents folder

Windows folder for storing user-created files.

Error Checking

Windows graphical tool that scans and fixes hard drive problems. Often referred to by the name of the executable, chkdsk, or Check Disk. The Mac OS X equivalent is the Disk Utility, and Linux offers a command-line tool called fsck.

Data collector Sets

Windows log repository that accepts log entries from other windows computers

pinned apps

Windows method of attaching programs to the taskbar. A pinned app gets a permanent icon displayed on the taskbar. Known as pinned porgrams in Windows 7

ODBC Data Source Administrator

Windows programming tool for configuring the Open Database Connectivity (ODBC) coding standard. Data Source Administrator enables you to create and manage entries called Data Source Names (DSNs) that point ODBC to a database. DSNs are used by ODBC-aware applications to query ODBC to find their databases

file association

Windows term for the proper program to open a particular file; for example, the file association for opening or .mp3 files might be Winamp.

Performance Monitor

Windows tool for tracking system resources over time

Windows Memory Diagnostic

Windows tool that can automatically scan a computer's RAM when a problem is encountered

Remote Desktop Connection

Windows tool used to form a remote desktop connection and graphically access the GUI of a remote system

Local Security Policy

Windows tool used to set local security policies on an individual system.

Resource monitor

Windows utility that displays detailed performance information about a computer's CPU, memory, disk, and network activity

Task Manager

Windows utility that shows all running programs, including hidden ones, and is accessed by pressing ctrl-shift-esc. You can use the Task Manager to shut down an unresponsive application that refuses to close normally

Server Message Block (SMB)

Windows' network file and print sharing protocol, though every major OS now supports it. Protocol of choice for LAN file servers. Uses TCP port 445 and UDP ports 137, 138, and 139

HDBaseT

Wired video transmission system to carry uncompressed HD video over Cat 5a or Cat 6 network cables

IEEE 802.11

Wireless Ethernet standard more commonly known as Wi-Fi.

GSM (Global System for Mobile Communications)

Wireless data standard for mobile devices

infrastructure mode

Wireless networking mode that uses one or more WAPs to connect the wireless network nodes to a wired network segment.

802.11b

Wireless networking standard that operates in the 2.4 GHz band with a theoretical maximum throughput of 11 Mbps

802.11g

Wireless networking standard that operates in the 2.4-GHz band with a theoretical maximum throughput of 54 Mbps and is backward compatible with 802.11b

802.11a

Wireless networking standard that operates in the 5-GHz band with a theoretical throughput of 54 Mbps

WEP (Wired Equivalent Privacy)

Wireless security protocol that uses a standard 40-bit encryption to scramble data packets. Does not provide complete end-to-end encryption and is vulnerable to attack.

WPA (WIFI protected access)

Wireless security protocol that uses encryption key integrity-checking/TKIP and EAP and is designed to improve on WEP's weaknesses. Supplanted by WPA2

WPA2 (Wi-Fi Protected Access 2)

Wireless security protocol, also known as IEEE 802.11i. Uses the Advanced Encryption Standard (AES) and replaces WPA

Bluetooth

Wireless technology designed to create small wireless networks preconfigured to do specific jobs, but not meant to replace full-function networks or Wi-Fi.

Radio Frequency Identification (RFID)

Wireless technology that uses small tags containing small amounts of digital information, and readers capable of accessing it. Passive RFID tags operate by harvesting some of the power a scanner or reader emits, enabling a vast array of applications. Common uses such as tracking inventory, identifying lost pets, contactless payments, authentication, and wiresless door locks are just scratching the surface

T568A and B

Wiring standard for Ethernet cable

AOL

You've got mail!

IMEI (International Mobile Equipment Identity)

a 15-digit number used to uniquely identify a mobile device, typically a smartphone or other device that connects to a cellular network.

file

a named collection of any form of data that is stored beyond the time of execution of a single job. A file may contain program instructions or data, which may be numerical, textual, or graphical information

disk initialization

a process that places special information on every hard drive installed in a windows system

application

a program that enables you to perform a specific task on a computer, such as write a document or play a game

Disk Defragmenter

a program that maintains performance by rearranging chunks of data on a storage device to ensure chunks that comprise a file are store contiguously. Renamed to Optimize Drives in Windows 8 and up

barcode

a scannable, read-only binary code often used to mark items for inventory tracking

restore point

a snapshot of your computer configuration at a specific point in time, created by the System Restore utility and used to restore a malfunctioning system

checkpoint

also known as a snapshot. Saves changes to a virtual machine's state. Checkpoints are great for performing maintenance with a safety net, but they aren't a complete backup, and many snapshots can slow a VM down. Get rid of them when the danger has passed

directory

another name for a folder

ESD mat

antistatic mat

ESD strap

antistatic strap

bootable disk

any storage device with a self-starting operating system

biometric authentication

authentication process using bio-metric data such as voice, finger prints or retinal scans.

optimization

changes made to a system to improve its performance

edge LED backlighting

columns or rows of LEDs placed along the sides or top of a display panel to illuminate the display

del (erase)

command line tool used to delete/erase files

dir

command line tool used to display the entire contents of the current working directory

format

command line tool used to format a storage device

rd (rmdir)

command line tool used to remove directories

net use

command line utility in Windows net command enables a user to connect, disconnect, and view information about existing connections to network resources

md (mkdir)

command-line tool used to create directories

move

command-line tool used to move a file from one location to another

Cd

command-line utility for changing the focus of the command prompt from one directory to another. Shorthand for "change directory"

ping

command-line utility used to send a "ping" message to another computer, which can be used to verify another system is on the network, spot potential DNS issues, identify latency problems, and so on

Computer

commonly used interface for Windows Explorer that displays hard drives and devices with removable storage

trackball

point device used in early portable computers, distinguished by a ball that is rolled with the fingers

User Datagram Protocol (UDP)

connectionless protocol used with TCP/IP

power management

cooperation between hardware, BIOS, and OS to reduce power consumption

cp

copy command in linux

dis-intended capacitors

failed capacitors on a motherboard, which tend to bulge out at the top. This was especially a problem during the mid-2000s, when capacitor manufacturers released huge batches of bad capacitors

extension

file extension

destination port

in port triggering, the port that the router opens to receive a response after the router sends outbound traffic on the trigger port see trigger port

traceroute

macOS and Linux command-line utility for following the path a packet takes between hosts. The Windows version is named tracert

Time Machine

macOS backup tool that enables you to create full system backups, called local snapshots, and to recover some or all files in the event of a crash; it also enables you to restore deleted files and recover previous versions of files

Spaces

macOS feature of enabling multiple desktops

Utilities

macOS folder that contains tools for performing services on a Mac beyond what's included in System Preferences, including Activity Monitor and Terminal

Keychain

macOS password management and storage service that saves passwords for computer and non-computer environments. Also the iCloud Keychain adds synchronization among any macOS and iOS devices connected to the Internet for a user account

System preferences

macOS tool containing many administrative functions

launchd

macOS tool for automatically running tasks based on a schedule

frequency

measure of a sound's tone, either high or low

hotspot

mobile hotspot

change

modify configuration or status of a system, such as updating an NTFS permission or modifying a password

su

older linux command for gaining root access

host (networking)

on a TCP/IP network, a single device that has an IP address-any device (usually a computer) that can be the source or destination of a data packet. In the mainfram world, computer that is made available for use by multiple people simultaneously. Also, in virtualization, a computer running on or more virtual operating systems

insert mode

one of two modes (along with command mode) used in vi. enables typing input to the document. see vi

spoofing

pretending to be someone else by placing false information into packets. Commonly spoofed data include a source MAC address or IP address, e-mail address, Web address, or user name. Generally a useful tool for enhancing or advancing other attacks, such as social engineering or spear fishing

deframentation (defrag)

procedure in which all the files on a hard drive are rewritten on disk so that all parts of each file reside in contiguous clusters. The result is an improvement in disk speed during retrieval operations

primary charge roller

replaces the primary corona wire in newer laser printers. The roller, which is very close to the photosensitive drum, is given a very high charge, forming an electric field (corona) and passing a charge to the photosensitive drum

code

set of symbols representing characters (ACII code) or instructions in a computer program (a programmer writes source code, which must be translated into executable or machine code for the computer to use).

address bus

set of wires leading from the CPU to the memory controller chip (traditionally the northbridge) that enables the CPU to address RAM. Also used by the CPU for I/O addressing. On current CPUs with built-in memory controllers, the address bus refers to the internal electronic channel from the microprocessor to RAM, along which the addresses of memory storage locations are transmitted. Like a post office box, each memory location has a distinct number or address; the address bus provides the means by which the microprocessor can access every location in memory

IRQ (Interrupt Request)

signal from a hardware device, such as a modem or a mouse, indicating that it needs the CPU's attention. In PCs, IRQs are sent along specific IRQ channels associated with a particular device. IRQ conflicts were a common problem in the past when adding expansion boards, but the plug-and-play specification has removed this headache in most cases.

cable lock

simple anti-theft device for securing a laptop to a nearby object

ink cartidge

small container of ink for inkjet printers

satellite latency

small signal delay caused by the distance traveled by satellite signals

codec (compressor/decompressor)

software that compresses or decompresses media streams

honesty

telling the truth

color depth (scanner)

term to define a scanners ability to produce color, hue, and shade

bandwidth

the capacity of a network to transmit a given amount of data during a given period

color depth (display)

the number of bits (bit depth) necessary to represent the number of colors in a graphics mode. Common color bit depths are 16-bit and 32-bit, representing 65,536 colors and 16.7 million colors (plus an 8-bit alpha channel for transparency levels), repectively

radio frequency RF

the part of the electromagnetic spectrum used for radio communication

syntax (command)

the proper way to write a command-line command so that it functions and does what it's supposed to do

attack vector

the route or methods used by a given attack (including malware)

host (virtualization)

the system running (or hosting) a virtual machine

electric potential

the voltage differential between any two objects, one of which is frequently ground or earth, resulting in a degree of attraction for the electrons to move from one of the objects to the other. A large difference between a person and a doorknob, for example, can lead to a shocking experience when the two touch. see electrostatic discharge

heat dope

thermal compound

registration (product)

usually optional process that identifies the legal owner/user of the product to the supplier

Display Settings

windows 10 utility that enables a user to change color schemes, font sizes, and other aspects of what appears on the computer monitor

Users folder

windows default location for content specific to each user account on a computer. It is divided into several folders such as Documents, Pictures, Music, and Videos

802.11n

wireless networking standard that can operate in both the 2.4-GHz and 5-GHz bands and uses multiple in/multiple out (MIMO) to achieve a theoretical maximum throughput of 100+ Mbps