D 386 design systems chapter 2

Which operating system allows for its source code to be modified and redistributed?

Android

Which type of processor memory is located on the processor itself?

Level 1 cache

northbridge

The northbridge connects the southbridge to the CPU. It is often referred to as the memory controller hub. It handles the faster components on the motherboard, including RAM, ROM, basic input/output system (BIOS), accelerated graphics port (AGP), PCI Express, and the southbridge chip as well as the CPU.

What is a key reason to implement a RAID 0 disk configuration?

To improve overall disk performance

What is the primary function of the file system interface?

To provide a way for the system to access and use files

Why do applications designed to work on one operating system not work on a different operating system?

unique system calls

Which processors process in both 32 and 64 bits?

x86-64 processors

OS life cycle

-An operating system in alpha is a first draft of an operating system. Operatingsystems that are available in alpha are considered previews. It is common to find these inopen source communities, such as Linux operating systems, but it is uncommon to find acorporate-based operating system in alpha. -An operating system in beta is a second draft of an operating system. This stageof an operating system means most of the bugs have been discovered and are avidlybeing patched. This stage is typically used to discover missing features and new bugs.Some operating system developers require an opt-in to run a beta operating system, andsome require invites to a beta program that mandates participation -An operating system that is deemed a release candidate is in thefinal stage before it is released to market. During the release candidate stage, administra-tors are urged to install and use the operating system as though it were the final release.The benefit is that the administrator can get a previewed look at the operating systemwhile helping to polish the final product, also called the release to market (RTM). Anoperating system in this stage is generally stable and has relatively few bugs -A current operating system, as the term states, is the current release of anoperating system. Many operating system developers are on a one- to two-year releasecycle for the future version of the current operating system.

version

A version is a particular revision of a piece of software, normally describedby a number that tells you how new the product is in relation to other versions ofthe product.

cpu components

ALU - where arithmetic and Boolean logical calculations are performed. control unit - which controls the processing of instructions and the movement of internal CPU data from one part of the CPU to another. memory.The interface unit, which moves program instructions and data between the CPU and other hardware components.

peripherals

All the items mentioned, except for the CPU, memory, and power source, are considered peripheral (that is, external) to the main processing function of the computer itself and are known, therefore, as peripherals.

RAID 1

Also known as disk mirroring, RAID 1 is a method of producing fault tol-erance by writing all data simultaneously to two separate drives. If one drive fails, theother contains all of the data, and it will become the primary drive. Disk mirroringdoesn't help access speed, however, and the cost is double that of a single drive. If a sep-arate host adapter is used for the second drive, the term duplexing is attributed to RAID1. Only two drives can be used in a RAID 1 array.

Operating system

An operating system (OS), sometimes called system software, is a computer system's central and most important component. It organizes and manages the major functions of the computer, such as input, output, processing, storage, and memory. Depending on the brand of computer, e.g. PC or Apple computers, different operating systems such as Windows 10 or OS X will be installed. These operating systems are considered proprietary system software, each with its own customized features such as graphical user interfaces (GUIs), 32-bit or 64-bit operating systems, and random access memory (RAM). Operating systems and their collective features enable the computer's hardware devices and application software to work together.

ADRAM

Asynchronous DRAM (ADRAM) is characterized by its independence from the CPU'sexternal clock.

secondary storage

Below the level of conventional memory, storage in the hierarchy is not immediately available to the CPU, is referred to as secondary storage, and is treated as I/O. One important advantage of secondary storage, of course, is its permanence, or nonvolatility. As noted in Chapter 7, RAM data is lost when the power is shut off. Flash memory uses a special type of transistor that can hold data indefinitely without power. The magnetic media used for disk and tape and the optical media used for DVD and CD also retain data indefinitely. Secondary storage has the additional advantage that it may be used to store massive amounts of data. Even though RAM is relatively inexpensive, disk and tape storage is much cheaper yet. Large amounts of online secondary storage may be provided at low cost. Current hard disks store data at a density of more than 100 Gbits per square centimeter! Tape, most flash memory devices, optical disks, and many magnetic disks are designed for easy removal from the computer system, which makes them well suited for backup and for off‐line storage of data that can be loaded when the data is needed. This provides the additional advantage that secondary storage may be used for off‐line archiving, for moving data easily from machine to machine, and for off‐line backup storage. For example, a flash memory card may be used to store digital camera photographs until they are moved to a computer for long‐term storage; similarly, a removable hard disk can be used to move large amounts of data between computers.

emulator

By definition, an emulator is a utility program that allows applications designed for one hardware environment to run in a different hardware environment.

How do computers avoid burdening the main central processing unit (CPU) with programmed I/O (PIO)?

By offloading to a direct-memory-access (DMA) controller

call instructions

CALL instructions, sometimes known as JUMP SUBROUTINE instructions, are used to implement function, subroutine, procedure, and method calls. Thus, CALL instructions are important as a means to enable program modularization.

A client is utilizing servers, data storage, data backup, and software development platforms over an internet connection.

Cloud computing

types of memory packaging

DIMM (dual in-line memory module) - Desktop computers will use DIMM SODIMM (small outline dual in-line memory module - Laptops and smaller devices require SODIMMs orsmaller memory packaging

DRAM

DRAM is dynamic random access memory. This is what most people are talking about whenthey mention RAM. When you expand the memory in a computer, you are adding DRAMchips. You use DRAM to expand the memory in the computer because it's a cheaper type ofmemory. Dynamic RAM chips are cheaper to manufacture than most other types becausethey are less complex. Dynamic refers to the memory chips' need for a constant updatesignal (also called a refresh signal) in order to keep the information that is written there. Ifthis signal is not received every so often, the information will bleed off and cease to exist.

DDR SDRAM

Double data rate (DDR) SDRAM earns its name by doubling thetransfer rate of ordinary SDRAM; it does so by double-pumping the data, which meanstransferring a bit per pin on both the rising and falling edges of the clock signal.

Drivers

Drivers are extremely specific software written for the purpose of instructing aparticular OS on how to access a piece of hardware

virtualization

Generally, with a virtual machine, guest operating systems and applications run in an environment that appears to them to be native hardware and that behaves toward them as native hardware would but that also protects, manages, and limits them.

HDD

Hard disk drive (HDD) systems (or hard drives for short) are used for permanent storageand quick access

chipset

In a computer system, a chipset is a set of electronic components in one or more integrated circuits known as a "Data Flow Management System" that manages the data flow between the processor, memory and peripherals. It is usually found on the motherboard. two types of chipsets: northbridge and southbridge

Which ability describes a security feature in virtualization?

Isolating the operating system when running multiple concurrent VMs

What is the function of the operating system

It acts as an intermediary between computer users and computer resources.

Which cache memory is the smallest but fastest?

L1

Which problem is managed by implementing a file system?

Logical structure for organizing and storing files on a storage device

What is a disadvantage of solid-state drives (SSD) when compared to hard disk drives (HDD)?

Longevity

CPU

Modern central processing units (CPUs) perform billions of tasks per second, making them extremely powerful components. Though the CPU and system memory are separated physically and functionally, they are intimately related and are key factors in the processing speed, efficiency, and overall operation of a computer system. Two factors determine the capacity of memory in a computer system: (1) the number of bits in the memory address register (MAR) and (2) the number of bits in the address field of the instruction set, which establishes how many memory locations can be directly addressed from the instruction. In today's IT industry, random-access memory (RAM) is the primary memory installed in most computer systems. Additionally, most computers have a mix of static RAM (SRAM) and dynamic RAM (DRAM). SRAM is the faster of the two and does not need to be refreshed, while DRAM is less expensive and has more room for data but needs electric refreshing. Ironically, they both are volatile and lose their contents when powered off.

What is the next step to be performed to address storage drive issues after identifying recent changes and breaking down large problems?

Perform a system backup.

SRAM

Static random access memory (SRAM) doesn't require a refresh signal like DRAM does. Thechips are more complex and are thus more expensive. However, they are considerably faster.DRAM access times come in at 40 nanoseconds (ns) or more; SRAM has access times fasterthan 10ns. SRAM is classically used for cache memory

storage devices

Storage devices contain most of the files that computer operating systems need and manage. The main mass-storage system in modern computers is secondary storage. The hard disk drive (HDD) is the computer systems' de facto device for mass storage, as it is internal to the system unit and holds all programs, files, and data. The HDD is also classified as a nonvolatile storage device (NVS), indicating that the storage device will not lose data during a power outage or similar event. In conjunction with an NVS device, a nonvolatile memory (NVM) device is also used as a mass storage option based on its design of circuits and electric charges that guard against data loss. Solid-state disks (SSD) are an example of NVM devices. While HDDs and SSDs are used for storage, their designs are drastically different. As the name implies, SSDs have no moving parts. Also, they are more efficient with no need to seek time or rotational latency, which is prevalent in HDDs. HDDs are also prone to failure in their moving parts (disk platters, rotating spindles, and arm assembly).

SDRAM

Synchronous DRAM (SDRAM) shares a common clock signal with the computer's system-bus clock, which provides the common signal that all local-bus components use for each stepthat they perform. This characteristic ties SDRAM to the speed of the FSB and hence theprocessor, eliminating the need to configure the CPU to wait for the memory to catch up.

system calls

System calls are a unique set of services provided by operating systems for use by applications and have to be accounted for by different operating systems.

bottom and top of stack

The "bottom" of the stack is a fixed memory location, and a stack pointer points to the "top" of the stack,

dma controller

The DMA controller directs data between devices and system memory, making the operation between the two devices look like a single operation. For example, if a computer wants to send data from system memory to a printer, it issues a DMA transfer request to the printer's DMA controller.

shortened operating system definition

The OS provides users with an interface with the computer so that they can send commands (input) and receive feedback or results(output). To do this, the OS must communicate with the computer hardware to perform the following tasks ■ Disk storage and file management ■ Device access ■ Memory management ■ Output formatting

A client has recently purchased a CPU that references the amount of L1 cache in the list of features. What is this referring to?

The amount of memory residing directly on the processor die

clock

The clock provides a master control as to when each step in the instruction cycle takes place. The pulses of the clock are separated sufficiently to assure that each step has time to complete, with the data settled down, before the results of that step are required by the next step. Thus, use of a faster clock alone does not work if the circuitry cannot keep up.

fetch - execution cycle

The fetch-execution instruction cycle is the basis for every capability of the computer. This seems like a strong statement, but think about it: the purpose of the computer is to execute instructions similar to those that we have already introduced. And, as you've already seen from the Little Man Computer, the operation of every instruction is defined by its fetch-execute instruction cycle. Ultimately, the operation of a computer as a whole is defined by the primary operations that can be performed with registers, as explained in Section 7.2: to move data between registers, to add or subtract data to a register, to shift data within a register, and to test the value in a register for certain conditions, such as negative, positive, or zero

hypervisor

The hypervisor, also known as the virtual machine manager, is responsible for creating and managing a virtual machine.

l3 cache

specialized memory developed to improve the performance of L1 and L2. L1 or L2 can be significantly faster than L3, though L3 is usually double the speed of DRAM. With multicore processors, each core can have dedicated L1 and L2 cache, but they can share an L3 cache.

What is a key similarity between RAM and memory cards?

they are both solid state

What is a feature of cloud-based operating systems?

they are primarily stateless

Which type of memory packaging can support quad, triple, and dual channels?

DDR3 DIMM

What is a temporary holding area for data and programs?

RAM

four types of operating systems

-Server operating systems allow for the sharing of information and applicationsby workstation operating systems. The operating system is optimized for backgroundprocesses used for access by clients, as opposed to the foreground processes, suchas the GUI -Workstation operating systems allow end users to access informationand applications on server operating systems as well as independently run applicationslocally. The operating system is optimized for foreground processes, such as the GUI.Background sharing is usually limited to a specific number of users; workstation ver-sions of Microsoft Windows are limited to 10 concurrent users -Mobile operating systems are found on mobile devices such as phones andtablets. The mobile operating system is generally optimized for touch-based deviceswhere one program is used at a time -Cloud-based operating systems are a new breed of operating systemthat has emerged from the mobile computing era. Cloud-based operating systems arealso considered stateless operating systems, since personal data is not primarily storedon the device but in the cloud. Mobile operating systems can be considered cloud-based operating systems. So this category takes on a dual role of defining a categoryand describing where the data is stored. The Chrome operating system is not a mobileoperating system and fits into this category.

classifications of operating systems

-single‐user systems, which are considered multitasking systems, are found in laptops and workstations -mobile device operating systems for small handheld devices, smartphones, e-readers, and tablets that can provide single-user and multitasking at a scaled-down level due to power and memory limitations, etc.; -mainframe systems that manage large-scale platforms and enterprise environments that require large amounts of storage, memory, and computing; -network server systems are designed and named for a specific purpose such as database servers, web servers, and print servers; -real‐time systems that are designed to direct CPU access immediately when needed or required; -embedded control systems that are specialized operating systems designed to control a single piece of equipment or machinery; and -distributed systems that are geared toward allocating process power, programs, files, and databases to network users.

Which size data path do today's DIMMS use?

64 bit

byte

8 bits

32 bit processors

A 32-bit operating system is one that can not only run on a 32-bit processorbut can utilize the capabilities of the processor fully. While this may sound simple, thetruth of the matter is that it took many years after the 32-bit processor became availablebefore operating systems (which were 16-bit at the time) were able to utilize their fea-tures. You cannot execute 64-bit software on 32-bit operating systems; the instructionssets are functionally different.

64 bit processor

A 64-bit operating system is one that is written to utilize the instructions pos-sible with 64-bit processors. Originally, these were more common with servers thandesktops, but they have now become ubiquitous in the market with both Intel and AMDprocessors. As mentioned earlier, you cannot mix 64-bit software with 32-bit hardware(but you can run most 32-bit software on 64-bit hardware).

branch

A branch is an instruction in a computer program that can cause a computer to begin executing a different instruction sequence and thus deviate from its default behavior of executing instructions in order. 3 types of branch call jump return

What is one reason why programmed I/O does not work well when the I/O device is a hard disk or a graphics display?

A complete instruction fetch-execute cycle must be performed to transfer each I/O data word.

GUI

A graphical user interface, or GUI, is a method by which aperson communicates with a computer using graphical images, icons, and methodsother than text. GUIs allow a user to use a mouse, touchpad, or another mechanism(in addition to the keyboard) to interact with the computer to issue commands

l2 cache memory

A memory bank built into the CPU chip, packaged within the same module or built on the motherboard. The L2 cache feeds the L1 cache, which feeds the processor. L2 memory is slower than L1 memory. See cache.

network

A network is any group of computers that have a communication link bet-ween them. Networks allow computers to share information and resources quicklyand securely.

register

A register is a single, permanent storage location within the CPU used for a particular, defined purpose. A register is used to hold a binary value temporarily for storage, for manipulation, and/or for simple calculations. Note that each register is wired within the CPU to perform its specific role. That is, unlike memory, where every address is just like every other address, each register serves a particular purpose. The register's size, the way it is wired, and even the operations that take place in the register reflect the specific function that the register performs in the computer.

shell

A shell is a program that runs on top of the OS and allows the user to issue commands through a set of menus or another interface (which may or may not. be graphical). Shells make an OS easier to use by changing the user interface. Exploreris the name of the shell that has been used with the Windows operating system sinceWindows 95

stack

A stack is used to store data when the most recently used data will also be the first needed. For that reason, stacks are also known as LIFO, for last‐in, first‐out, structures. As an analogy, stacks are frequently described by the way plates are stored and used in a cafeteria. New plates are added to the top of the stack, or pushed, and plates already on the stack move down to make room for them. Plates are removed from the top of the stack, or popped, so that the last plates placed on the stack are the first removed. Similarly, the last number entered onto a computer memory stack will be the first number available when the stack is next accessed. Any data that must be retrieved in reverse order from the way it was entered is a candidate for the use of stacks

program control instructions

Program control instructions control the flow of a program. Program control instructions include jumps and branches, both unconditional and conditional, and also CALL and RETURN instructions.

RAID 0

RAID 0 is also known as disk striping, where a striped set of equal spacefrom at least two drives creates a larger volume. This is in contrast to unequal space onmultiple disks being used to create a simple volume set, which is not RAID 0. RAID 0doesn't provide the fault tolerance implied by the redundant component of the name.Data is written across multiple drives, so one drive can be reading or writing whileanother drive's read-write head is moving. This makes for faster data access. If any oneof the drives fails, however, all content is lost. Some form of redundancy or fault toler-ance should be used in concert with RAID 0. Minumum of 2 drives required.

A client recently experienced a hard drive failure and lost stored data. The client does not want to rely on a backup but does want to secure their data. Which RAID configuration does this client need?

RAID 1

RAID 5

RAID 5 combines the benefits of both RAID 0 and RAID 1, creating a redun-dant striped volume set. Sometimes you will hear it called a stripe set with parity. UnlikeRAID 1, however, RAID 5 does not employ mirroring for redundancy. Each stripe placesdata on n-1 disks, and parity computed from the data is placed on the remaining disk.The parity is interleaved across all the drives in the array so that neighboring stripeshave parity on different disks. If one drive fails, the parity information for the stripesthat lost data can be used with the remaining data from the working drives to derivewhat was on the failed drive and to rebuild the set once the drive is replaced. RAID 5 does not offer "mirroring"; therefore, more drives are required to recompute parity in the event of drive failure. Minimum of 3 drives required.

ROM

ROM stands for read-only memory. It is called read-only because you could not write to theoriginal form of this memory. Once information had been etched on a silicon chip and man-ufactured into the ROM package, the information couldn't be changed. Some form of ROMis normally used to store the computer's BIOS because this information normally does notchange often

Which systems are types of operating systems?

Real-Time Systems

What is an example of a server operating system?

Red Hat Enterprise Linux

RAID storage

Redundant arrays of independent disks (RAID) is a concept that evolved out of smaller and cheaper storage devices being leveraged to improve data rates and reliability. More accurately, RAID is a set of strategies for using more than one storage drive in a computer system. Broadly, the two most popular configurations are RAID 0 and RAID 1. In RAID 0 configuration, every time data is written to a hard drive, it is spread across two physical drives, so it mostly favors performance. In RAID 1 configuration, all the data written to one drive is perfectly mirrored and written to a second drive, therefore lending itself to a backup or mirroring.

registers and buffers

Registers and buffers hold data and amplify a signal before the data is written to the module.

Which type of DRAM do modern laptops all use?

SO-DIMM

Which type of storage devices are characterized by the fastest access times and data transfer rates?

SSD drives

benefits of virtualization

Several advantages make virtualization attractive. Most of them are fundamentally related to the ability to share the same hardware yet run several different execution environments (that is, different operating systems) concurrently. One important advantage of virtualization is that the host system is protected from the virtual machines, just as the virtual machines are protected from each other. A virus inside a guest operating system might damage that operating system but is unlikely to affect the host or the other guests. Because each virtual machine is almost completely isolated from all other virtual machines, there are almost no protection problems. ne feature common to most virtualization implementations is the ability to freeze, or suspend, a running virtual machine. Many operating systems provide that basic feature for processes, but VMMs go one step further and allow copies and snapshots to be made of the guest. The copy can be used to create a new VM or to move a VM from one machine to another with its current state intact. The guest can then resume where it was, as if on its original machine, creating a clone. The snapshot records a point in time, and the guest can be reset to that point if necessary (for example, if a change was made but is no longer wanted). Often, VMMs allow many snapshots to be taken. For example, snapshots might record a guest's state every day for a month, making restoration to any of those snapshot states possible. These abilities are used to good advantage in virtual environments. A virtual machine system is a perfect vehicle for operating-system research and development. Normally, changing an operating system is a difficult task. Operating systems are large and complex programs, and a change in one part may cause obscure bugs to appear in some other part. The power of the operating system makes changing it particularly dangerous. Because the operating system executes in kernel mode, a wrong change in a pointer could cause an error that would destroy the entire file system. Thus, it is necessary to test all changes to the operating system carefully.

cache memory

Since the amount of cache memory is small compared to main storage, cache memory also has a speed advantage beyond the use of faster memory technology: just as it's faster and easier to find a particular address in a small town with a single main street, so it is faster and easier to locate an address in cache memory.

There are a number of different types of components of a motherboard. Which motherboard component is used for support of slower onboard peripherals?

Southbridge

IPO model

The input-process-output (IPO) model encompasses the principal function of an individual computer system. The tangible component of a computer system, the hardware, is composed of the central processing unit (CPU), memory, input devices (keyboards, mice, touch screens, and other wireless devices), and output devices (monitors, printers, etc.). The main processing functions of your computer take place in the CPU and memory, which typically reside on the main circuit board. Depending on suitability, various memory formats will be used in a computer system. A primary memory format, which is typically used to store working data, is random-access memory. Technically speaking, dynamic random-access memory (DRAM) is the most widely used random-access memory (RAM). Also located on the main circuit board is read-only memory (ROM). This memory format is responsible for holding the computer's start-up instructions. ROM is nonvolatile storage; therefore, its memory content is not lost or erased when powered off or during a power interruption.

primary storage

The main memory, often known as primary storage, working storage, or RAM (for random access memory), holds programs and data for access by the CPU. Primary storage is made up of a large number of cells, each numbered and individually addressable. Each cell holds a single binary number representing part of a data value or part of an instruction. The smallest addressable size of the cell in most current computers is 8 bits, known as a byte of memory. Eight bits of memory can only hold 256 different patterns, so neighboring cells in memory are nearly always combined to form groupings with a larger number of bits. In many systems, for example, 4 bytes of memory combine to form a 32‐bit word. Modern computers address memory at least 4 bytes (a "32‐bit" computer) or 8 bytes (a "64‐bit" computer) at a time to take advantage of larger instruction and data groupings.

hit ratio

The situation in which the request is not already present in cache memory is known as a miss. The ratio of hits to the total number of requests is known as the hit ratio.

source

The source code is the actual code that defines how a piece of software works. Computer operating systems can be open source, meaning that the OS can be examinedand modified by anyone, or they can be closed source, meaning that only an owner ordeveloper can modify or examine the code. As an example, Microsoft and macOS areclosed source operating systems and Linux is an open source operating system

SDD

Unlike conventional hard drives, solid-state drives (SSDs) have no moving parts—they usethe same solid-state memory technology found in the other forms of flash memory. You canthink of them as big versions of the flash drives that are so common. Because they have no moving parts, SSDs are capable of transferring data much morequickly than HDDs. Advantages of SDD include Faster start-up and read times ■ Less power consumption and heat produced ■ Silent operation ■ Generally more reliable because of a lack of moving parts ■ Less susceptible to damage from physical shock and heat production ■ Higher data density per square centimeterThe disadvantages of SSDs are as follows: ■ The technology to build an SSD is more expensive per byte. ■ All solid-state memory is limited to a finite number of write (including erase) operations.Lack of longevity could be an issue. As the technology matures, this is becoming less andless of a problem

Application

Used to accomplish a particular task, an application is software that iswritten to supplement the commands available to a particular OS.

Which memory type is stored on a drive and is referred to as a paging file?

Virtual RAM

Which feature of a solid-state drive's flash memory ensures that the logical block addressing does not always address the same physical block's drive?

Wear leveling

Virtual RAM

What is Virtual Memory? Virtual memory makes your computer think it has more memory than it actually has. Without it, programs that take up more RAM than your computer has will not work properly. Virtual memory helps this by copying data from your RAM to your hard disk (HDD or SSD) to free up space.

fans

When you turn on a computer, you will often hear lots of whirring. Contrary to popularopinion, the majority of the noise isn't coming from the hard disk (unless it's about to gobad). Most of this noise is coming from the various fans inside the computer. Fans provideairflow within the computer.

multiprocessing

a computer organization consisting of multiple CPUs directly connected together, sharing memory, major buses, and I/O.

l1 cache

a memory cache that is directly built into the microprocessor, which is used for storing the microprocessor's recently accessed information, thus it is also called the primary cache. It is also referred to as the internal cache or system cache.

types of cooling

ait cooling liquid cooling - here are two major classifications of liquid cooling systems in use with PCs today: all-in-one (AIO) coolers and custom loop systems. AIO systems are relatively easy to install—theyrequire about as much effort as a heat sink and fan—and comparably priced to similarlyeffective air systems. Figure 1.42 shows an example from Corsair, with the pump in frontand the fans behind it, attached to the radiator. The main benefit to liquid cooling is silence. Only one fan is needed: the fan on the radi-ator to cool the water. So, a liquid-cooled system can run extremely quietly.

heirarchy of storage fastest to slowest

as you go down list you increase access time but increase storage amount/unit cost registers cache memory(SRAM) conventional memory (DRAM) flash memory/solid state drive Hard disk drive optical disk drive magnetic tape cartrige/

What facilitates a guest system's ability to run applications designed for a different operating system?

emulator

Which component is responsible for creating and running a virtual machine instance on a host?

hypervisor

Which requirement should be understood when configuring a RAID 5 system for a client?

minimum of 3 drives can be used.

how do mobile operating systems operate

mobile operating systems operate in a cloud-based environment and mimic the single-user, multitasking behavior of workstation-based operating systems with less computing power.

Which part of a hard disk drive is responsible for storing actual data?

platters

There are two basic designs of computers

portable and stationary

types of fans

power supply fan, cpu fan, front intake fan, rear exhaust fan

Which attribute of DRAM must a technician or developer consider ahead of time?

refresh signal

What can a dual in-line memory module (DIMM) use to contain data as well as amplify a signal before writing the data to a module?

registers