ISDS

Instructions are executed by the CPU through 4 steps (Machine Cycle) or (Instructions Cycle)

-Fetching -Decoding -Executing -Storing Fetching and Decoding : performed by the CONTROL UNIT Executing and Storing : performed by the ALU

Types of Storage Devices:

-Internal & External Hard Drives -Solid State Drives -Optical Media

What hardware features are personally necessary to consider when buying a computer ?

-Platform: refers to the software or OS it uses -Hardware: varying types of processors, amounts of memory, storage devices... -Hardware Specifications: system requirements -Form Factor: refers to the shape and size of the computer -Add-On Devices: peripheral devices - can connect and extend the capability of a computer.

HDD (Hard Disk Drives)

-cheaper -available in large versions -made up of 1 or more disks called platters -platters store data as magnetic particles -when in use the platters spin - cant be moved when in use -not portable -fragile -more storage capacity

SSD (Solid State Drives)

-faster performance -more energy efficient -more durable and portable -type of FLASH MEMORY device -data stored on INTEGRATED CIRCUITS that dont have moving parts -more expensive -less likely to have issues or problems

Your Computers Display is not working:

-make sure your computer is plugged in and try to reboot the computer -try connecting another display that you know IS working -make sure your brightness is not all the way down.

Overheating caused by direct sunlight can damage...?

-screens -processor -hard drive

RAM (Random Access Memory)

-stored on one or more chips connected to the main circuit board of the computer (also referred to as the motherboard). -it temporarily stores data needed by the OS and apps that you use -when you start an app on your computer the apps instructions are transferred from the hard drive to RAM -contents of RAM are lost when power is removed.

In the Binary System.....

0s represent the absence of an electronic charge 1s indicate the presence of an electronic charge

How many bits are in a byte?

8

2 types of encoding schemes?

ASCII : max of 8 bits per character Unicode : can encode text in 8 - bit, 16 - bit, and 32 - bit.

Describe how computers represent Text...

Binary Code: a number system that uses 1s and 0s to form bits which them form bytes.

Interference is a common problem with ______ devices

Bluetooth and Wireless

Control Unit VS. Arithmetic Logic Unit (ALU)

CONTROL UNIT: manages the flow of instructions within the processors. ALU: responsible for performing arithmetic operations.

components of a computer

CPU Input Devices Output Devices Memory Storage Devices

Measuring the Performance of Computer Hardware:

Clockspeed Bus Speed Bus Width

Input Devices

Communicates instructions and commands to a computer keyboard touchscreen mouse credit card scanner scanner webcam mics game controller

Output devices

Conveys info. from the computer to the user. projectors printer speaker headphones

Types of RAM:

Dynamic RAM (DRAM): VOLITILE -memory needs to be constantly recharged or contents will be erased Static RAM (SRAM): VOLITILE -memory can be recharged less frequently than DRAM, but can be more expensive than DRAM Magnetorestive RAM (MRAM): NON-VOLITILE -memory uses magnetic charges to store contents and can retain its contents in the absence of power Flash Memory: NON-VOLITILE -fast type of memory that typically is less expensive than some other types of RAM, and can retain its contents in the absence of power.

Internal Hard drives are either ...

Hard Disk Drives or Solid State Drives

A Stylus is a .... ?

Input Device

PowerSupply (the block on your charging cable) does what?

It converts AC power (wall outlet) to DC power (what your device can use).

3 levels of CACHE

L1 CACHE: the smallest - built directly onto the processor chip but also very expensive. L2 CACHE: a little slower - but has a much larger capacity - also built onto the chip directly. L3 CACHE: The largest - often mounted on the motherboard (even though it is the slowest cache, it is still faster than RAM). RAM

Local Apps VS. Web Apps

LOCAL APPS: installed on your device can be used without internet WEB APPS: programs you access over the Internet using a browser (ex: google docs).

Search Engines and Search Sites are.....

NOT THE SAME THING. google is a search site that gives you ACCESS to a search engine.

An application programed to run on a specific app is called a ______ ?

Native App

a computer mouse tracks movement with an ?

Optical Sensor

Benchmarking is an evaluation of _____?

Performance

Installing Computer Hardware:

Plug-and-Play Device Driver: a program that controls a device attached to your computer, such as a printer.

Voice Recognition + Voice Synthesis are used together by...

SIRI and Google Voice

An operating system uses available storage on a startup disk for _____?

Storing Programs Storing Apps Virtual Memory

CPU (Central Processing Unit)

The Processor It carries out the instructions that operate a device A complex integrated circuit consisting of millions of electronic ports and is primarily responsible for converting INPUT (data) into meaningful OUTPUT (information) converts input to output!!!!! It does this with the CONTROL UNIT & the ARITHMETIC LOGIC UNIT Data travels in and out of the CPU through embedded wires called a BUS.

Mixed devices (input and output)

VR headset

CACHE (memory processing cache)

When a computer needs information the first place it looks is a CACHE: a temporary storage space for recently or frequently used data. -computers improve processing times with multiple memory caches on or near the central processor (CPU)

a BUS =

a BUS is an electronic channel that allows the CPU and various devices inside or attached to a computer to communicate

Voice Synthesizer

a device that converts text into speech -some OS have built in voice synthesizers -ex: windows narrator tool - can read text that appears on a screen aloud. -Text to Speech technology: analyses words and breaks them down into diff phonemes or basic sound units.

Natural Language Processing

a form of data input in which computers interpret and digitize spoken words or commands

A fitness track is an example of what kind of device?

a mixed device

Smart Grid

a network that links your electric meter to your local utility enables the power company to control your homes AC and save you money.

RFID Radio Frequency Identification Tag

a small radio antenna that transmits data from a memory chip to a nearby reader from data chip to reader

Peripherals

add-on devices

Virtual Memory

allows for an operating system to use the temporary space on a hard disk as a form of simulated RAM for running apps. If your computer runs low on RAM... it may need to swap the contents of RAM to and from the hard drive : when this takes place your computer is using Virtual Memory. -always keep atleast 15% of space free on a magnetic Hard Disk -always keep 20-25% on a solid state drive

Uniform Resource Locator URL

an address that identifies the location of the page on the internet

speech recognition does which of the following to understand your meaning :

analysis phonemes and considers context

Restore Points

backups of system settings, programs and driver configurations -but don't include data files -WONT restore deleted or modified documents

NFC Near Field Communication

behind contactless payment provides short range 2-way communication for contactless payment

GPU (graphics processing unit)

carries ou the manipulation and display of graphics on the screen

What factors affect performance of a laptop?

clock speed battery life processor cache

Phonemes

corresponding pre-recorded PHONEMES are combined to create the words that are played by text to speech tech.

Extreme Temp. threats...

heat and sun can damage screens and can make the hard drive expand extreme cold can drain battery and freeze your LCD screen

bottlenecking

if you have a fast CPU but the Bus Speed is Low.

a PROCESSOR CORE

is a unit on the processor with the circuitry necessary to execute instructions (processors with more cored perform better and are more expensive). (Multi-core processors).

Non-Volitile (memory)

memory that does NOT loose its contents when power is removed.

Volitile (memory)

memory that looses its contents when power is removed

ROM: Read Only Memory

permanently installed on your computer and is attached to the motherboard -provides the means of communication between the OS and the hardware devices.

Cookies

small text files placed on your computer when you visit a website

A _________ links an electric meter to a local utility

smart grid

The BUS SPEED and BUS WIDTH

the BUS WIDTH determines the speed at which data travels the wider the bus the more data can travel on it

ClockSpeed

the processors clock speed measures the speed at which it can execute instructions. -can be measured in either Megahertz or Gigahertz (megahertz: million of cycles per second) (gigahertz: billions of cycles per second)

Digital Pens

use optical technology instead of relying on contact with a screen or tablet.

Radio Frequency Connection (RF)

uses simple radio waves to transmit data -usually requires you to put a small RF receiver in the USB port.

Issues with you Peripheral Devices? ...

usually related to CONNECTIVITY. -is it plugged in? is it charged? connection cables in? -try restarting device and computer -try connecting and disconnecting from bluetooth