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Flashcards in Software and Hardware Deck (96):
1

Why is hardware and software necessary?

These are required because without one the other does not work as the software runs the hardware. Software tells the hard ware what to do and the hardware provides components that allow instructions to be executed.

2

System software

Essential software that provides a platform that gives the user an interface to control the hardware and run application software.

3

Application software

Non-essential software that allows a user to perform tasks such as games, word processors, web browsers etc.

4

What is the purpose of the Operating System (OS)?

Allows the user to interact with the hardware. Provides a user-friendly interface.

5

What are the functions of the Operating System (OS)?

Processor(s) management
Memory management
Input/output Device management
Applications management
Security management

6

What is Processor(s) management?

Many programs may be running at the dame tome. The activities that each program is performing are known as a process/ each process requires the use of the CPU but is only capable of executing one process at a time. The process manager prioritises the tasks and allocates time to each process- time slicing

7

What is Memory management?

The memory is in charge of the RAM. It will check that all requests from programs for memory space are valid and allocates accordingly

8

What is Input/output Device management?

The peripheral manager controls all input and output requests. These could include requests to use: printers, speakers, keyboard. It will communicate with the device through software called drivers. The driver translates the instructions into ones that can device can understand.

9

What is Applications management?

The application programs make use of the operating system by making requests for services through a defined application program interface (API). It manages the sharing of internal memory among multiple applications.

10

What is Security management?

OS controls access to the computer by allowing the user to set up login names and passwords. Allows file access control: read only files.

11

What is a utility program?

A program for carrying out a routine function.
The OS uses applications called utilities which allow the user to manage the computer. There are many different utility programs and they may vary across operating systems. They are often accessed via a special menu or control panel in the OS.

12

File Compressor

A file compression utility is a software program that is used to compress or decompress files

13

Disk Defragmenter

Disk Defragmenter is a utility in Microsoft Windows designed to increase access speed by rearranging files stored on a disk to occupy contiguous storage locations, a technique called defragmentation.

14

Firewall

Can be used to filter between trusted and untrusted networks and prevent programs from communicating through the use of ports. Controls the traffic.

15

Anti-virus

Detects and blocks/destroys viruses.

16

What is the purpose of a translator?

Translates computer programs written on different languages into machine code, so that they can be executes by the CPU.

17

application software General purpose:

Software is designed to provide a general set of features that a broad range of customers will find useful.
The most popular and widely used software is usually off-the-shelf e.g.
-Web browsers
-Applications i.e. Microsoft Office
-Games

18

Specialised application software

Generally designed to perform a specific function or task
Doesn’t contain unnecessary features
Examples:
-Accountancy
-Stock Control
-Booking Systems

19

Off-the-shelf application software

You can purchase the software immediately as it is available to buy ‘off-the-shelf’ in a range of stores
It may also be available to download immediately
General purpose software generally falls into the category and some specialised software

20

Bespoke application software

Also known as custom-made software
Is specially designed and written for a single organisation or group of users to meet their exact needs.
Businesses or scientific projects will often need bespoke software as the exact software needed may not exist.
This will therefore be specialised software

21

Advantages of Off-the-shelf

• It is relatively cheap
• It is easily available from most computer shops
• It will have been thoroughly tested so there won’t be any serious problems or bugs
• There will be lots of user support i.e. books, user guides, online help and discussion forums on the Internet

22

disadvantages of Off-the-shelf

• There will be a vast number of features that you may never use and therefore storage requirements of these applications is fairly large.

23

Advantages of Bespoke

• the company will get the exact software/system that they need
• the software will work exactly how they want it to work
• the software will only have the features that they specifically need in their business

24

Disadvantages of Bespoke

• it takes a long time to develop such a system
• it costs a great deal of money
• the company may need to employ a team of people such as business analysts, programmers, testers etc.
• there will be little in the way of user support and online help

25

What is Hardware?

Hardware refers to any component that has a physical presence.
If you can touch it then it is hardware

26

What is Software?

Software refers to computer programs which control how the hardware behaves.
Microsoft, the Operating System, Word processors, Databases, Games and utilities.

27

how does a simple computer system functions?

Data is input and converted into the computer’s internal representation by input devices the data is processed.
The results of the processing are converted from the computer’s internal representation and output by an output device
The data may be stored for later use or transmitted to another computer system while it is still in the computer’s internal representation.

28

What hard ware catagorys are there?

Input Devices
Processing Devices
Storage Devices
Communication Devices
Output Devices

29

What is the purpose of the CPU?

The purpose of the Central Processing Unit (CPU) is to execute program instructions
It can only process one task at a time.
The CPU can be described as the brain of the computer.

30

What are processing tasks?

It process data:
Searches
Sorts
Calculates
Makes decisions

31

Control Unit

1. Controls and monitors the hardware (e.g. Printer)
2. Controls the input and output of data so that the signals go to the right place at the right time
3. Controls the flow of data in the CPU

32

Arithmetic and Logic Unit (ALU)

1. Arithmetic part – performs calculations on the data
2. Logic part – deals with logic and comparisons (e.g. Is one value greater than another)

33

Immediate Access Store

This holds the data and instructions needed by the Control unit
CPU fetches data and programs kept on backing storage and stores them temporarily in the Immediate Access Store

34

What is a bus?

A bus is simply a set of wires along which data can be transmitted.

35

What is an Address?

An internal channel from the CPU to memory across which the addresses of data (not the data) are transmitted.
Information about where the memory is located.

36

What is Data?

An internal channel that carries data between a computer's central processing unit and its random-access memory.

37

What is Control?

The control bus carries commands from the CPU and returns status signals from the devices, for example if the data is being read or written to the device the appropriate line (read or write) will be active.
Whether it is a read or write operation.

38

What is stored in main memory?

Instructions – the programs
Data – user data that has been entered
He thought to save programs in the memory. He also thought instructions and data were different things.

39

What needs to be loaded?

Data and Computer Programs (which contain instructions) are loaded into Main memory (RAM) by the operating system

40

FETCH

1. CPU fetches data and instructions from main memory and stores them in registers.
2. A register is a temporary internal memory area within the CPU
3. For this to happen, the CPU uses a hardware path known as the address bus.
The CPU places the address of the next instruction to be fetched on the address bus.
4. Data from this address moves from main memory into the CPU via another hardware path called the data bus
Gets the next instruction from memory and increment the program counter.

41

DECODE

The bit pattern into the instruction register

42

EXECUTE

-Data processing actually takes place
-The instruction is carried out
-The result of the processing is stored in yet another register

The action of the instruction into the instruction memory.

43

What is cache?

Cache is a small amount of memory which is a part of the CPU

44

What is the clock speed?

The speed at which the CPU can carry out instructions is called the clock speed. This is controlled by a clock. With every tick of the clock, the CPU fetches and executes one instruction. The clock speed is measured in cycles per second, and one cycle per second is known as 1 hertz. This means that a CPU with a clock speed of 2 gigahertz (GHz) can carry out two thousand million (or two billion) cycles per second.

45

What is clock speed measured in?

Clock speed is usually measured in MHz

46

What is benchmarking?

Benchmarking is a test used to assess the performance of a computer.
An example of this is Geek bench

47

What 5 CPU factors are taking into consideration when considering performance?

There are five key factors about CPU architecture that affect its performance: Cores Clock speed Cache size Processor type Bus width

48

RISC

RISC-Reduced instruction set computer
Instructions – RISC has a limited instruction set
Physical size- RISC is designed for mobile devices
Speed- RISC run at a lower clock speed
Energy consumption- RISC use less power
Cost- RISC is cheaper

49

CISC

CISC- Complex instruction set computer
Design- CISC has a heat sink and fan

50

Clock Speed

With every tick of the clock the CPU handles one piece of data or executes 1 instructions. Clock speed is measured in “cycles per second”. 1 cycle per second = 1 hertz
A computer running at 1 Gigahertz can execute 1 billion instructions per second. If you over clock the computer can overheat and shorten the life span. Also, it makes it unreliable.

51

Number of Cores

If you cannot speed up the clock anymore, then a sensible way forward if to use more than 1 CPU at the same time. Each CPU can execute instructions independently.
Dual core= 2 CPUs
Quad Core= 4 CPUs The more CPUs the device has the more power it needs which costs more. Therefore, it will have a low battery life.
Only need more cores if you want to render video or audio as they can be done in parallel with the other CPUs.
Sometimes one CPU is better than more.

52

Cache

Most data is stored on a hard disk. When we want to move or use data, we move it to RAM because it is faster RAM is still not fast enough to deal with data at the speed the CPU needs it. CPU has a Cache memory.
Cache memory is faster than RAM. Cache is extremely fast.

53

Word Length

This is the amount of bits that the processor can manipulate in one go.
Increasing the word size means more data can be manipulated at a greater speed.
Common word lengths are 32 and 64 bits.

54

Bus Width

Ideally the bus should match the work length so that sufficient data can be transferred to the processor
A 64 bit bus with a 32 bit bus will requires two transfers before the processors capacity it is met.

55

What is memory?

The part of a computer that stores data.
Stores program operations and data while a program is being executed. There are several types of memory, including: registers, cache, RAM and virtual memory.

56

Why do we need memory?

Without memory the computer would need to constantly access information from the hard drive. Memory is fast secondary storage is much slower. Without memory the computer would run much much much slower.

57

RAM

Random access memory,
Called working memory,
Stores programs and files currently in use. E.g. documents, presentations, operating system.
Volatile
The working space in which in which the computer stores data in current use.

58

NVRAM

Non-volatile RAM
Stores BIOS (Basic input output system. Checks it is all working.) settings used on start-up
Uses flash memory.
Hands over to boot loader.

59

ROM

Read only memory
Non-volatile
Chip cannot be changed.
Holds computer start up instructions.
Provides the computer with instructions that do not change- such as a boot set-up

60

Cache

Very fast memory that is close to the processor
Holds frequently used instructions and data.
Very expensive.
Cache memory is a form of buffer because the CPU works faster than the RAM. Stores frequently used instruction so it runs faster.

61

Flash

Electrical (solid state) memory
No moving parts so it is more robust and reliable than other storage
Large capacity.

62

Registers

Very fast storage area close to the CPU
Small storage capacity
Some registers are used for specific purposes while others are general purpose.

63

Volatile

Is computer memory that requires power to maintain the stored information; it retains its contents while powered on but when the power is interrupted, the stored data is quickly lost.
Once power source is removed you lose the information stored
RAM

64

Non-Volatile

Contents retained when power source removed. ROM

65

What are there different types of memory?

The speed of a modern CPU necessitates access to large amounts of data in order to maximize their performance.
If data is not provided it will stop and wait.
The problem that computer designs face is that memory that can keep up with 1-gigahertz CPU id extremely expensive.
They have solved the cost problem but tiering memory- using expensive memory in small quantities and then backing it up with larger quantities of less expensive memory.

66

What is virtual memory?

Used to free RAM
Areas of ram that have not been used recently are copied to the hard disk
Over use id called ‘thrashing’ and will significantly affect performance.

67

Memory is often referred to as a ‘buffer’. Explain what this means.

It stores data temporarily for a short period of time just before it is used.
Buffers are often used to smooth the transition of data between components that operate at different speeds.
By constantly filling the buffer the CPU can operate faster speeds as it has a steady flow to data.

68

What is secondary storage?

Secondary storage is a storage device that enables permanent data storage.

I anything that stores data other than in a temporary storage (RAM)
Non-volatile
It is not constantly accessed by the CPU
In a PC this tends to be a hard drive and removable media

69

By what other names can it be referred?

Auxiliary storage, External storage.

70

What are the main uses of secondary storage?

Storing programs and data.
Backing up data.
Adding additional storage.
Transferring files between computers.
Shared network storage.

71

Magnetic Disk advantages

-Cheap per MB
-Large storage capacity
-Faster than optical disk
-Can easily be replaced and upgraded

72

Magnetic Disk disadvantages

-Will eventually fail because of moving parts
-crashes can damage surface of disk therefore loosing data
-easily damaged
-can be noisy
-needs a large amount of power

73

Magnetic Tape advantages

-Very large capacity
-Reliable
-Less power
-Ease of storage and use

74

Magnetic Tape disadvantages

-Sequential access therefore slow to recover data
-Now more expensive
-Tape degradation over time

75

Optical Storage advantages

Easy to store and carry
-Easy to use
-Can be long-lasting

76

Optical Storage disadvantages

-Some are written once
-Needs an optical drive
-Expensive
-Easily broken/damaged

77

Solid-state disk advantages

-Fast,
-Durable
-Lightweight
-silent
-non-volatile
-needs less power
-no mechanical problems

78

Solid-state disk disadvantages

-Less capacity
-Can only be erased and written about 100,000 times.
-expensive

79

USB Pen Drive advantages

-Small
-Portable
-lightweight
-non-volatile
- no internal power
-durable
-Quick and tidy to edit files
-no mechanical problems
-require less power

80

USB Pen Drive disadvantages

-Expensive
-can break easily
-Easy to lose
-Can corrupt and lose all data

81

Flash Memory Card advantages

-Small
-Portable
-lightweight
-non-volatile
- no internal power
-durable
-Quick and tidy to edit files
-no mechanical problems
-require less power

82

Flash Memory Card disadvantages

-Expensive
-can break easily
-Easy to lose
-Can corrupt and lose all data
Different formats and sizes, making them often suited to one device and hard to read across all devices.

83

Magnetic Disk

Used in a desktop computer for storing items.
Server.
Computer with a lot of data.
Games controller.

84

Magnetic Tape

Back-up that don’t need to be accessed frequently of quickly.

85

Optical Storage

Commercially: Music, movies, games. (CD DVD)
Mass produced and cheap.

86

Solid-state disk

Back-up
When you want your computer/laptop to be fast.
High priced computers.
Mobile phones and tablets.
Some game controllers (Nintendo switch)

87

Flash Memory Card

Storing photos
Expanding game storage.
Most common uses are phones and cameras.
Android devices.

88

What is cloud storage?

It is storing and using services online, rather than storing them locally on a device such as a hard drive. Cloud storage is becoming more popular as web browsers become more powerful and network coverage is more widely available.

89

Cloud Storage Advantages

Can access the data from anywhere.
The provider backs up.
Good security.
Doesn’t require any power to store.
Cloud storage is cheap and some is free

90

Cloud Storage Disadvantages

Not 100% secure
Websites can be hacked.
If your internet connection is bad it will be really slow.
If you were working with a large files it is really slow.

91

Sequential Access

Each piece of data needs to read in sequence until the required data is located.

92

Direct Access

Also known as random access,
The exact file can be accesses directly without having to read any other files.

93

Solid State

Disk, USB, Flash Card

94

Magnetic

Disk, Tape

95

Optical

CD, DVD, Blu-ray Disk (BD)

96

How does changes in memory technologies lead to innovative computer designs?

Greater storage density; (the number of bits per chip has increased from almost 1 kilobit (Kb) to 2 gigabit (GB) per chip) meaning computer systems, in particular portable ones, can be much smaller.
Faster read/write times; allowing increases in the performance of computer systems, although these speed increases still lag behind the advances in processor speeds.
Less power consumption; allowing mains computers to consume less electricity and portable computing devices to last longer on battery power or use smaller batteries and be even more portable.
Lower costs per gigabit; making it affordable to install significant amounts of RAM in quite basic computer systems.
Flash memory capacity has risen to the point where solid state storage becomes a realistic alternative to the hard drive in smaller systems. This means that a computer can start operating far more quickly when it is started up as the data can be copied into RAM so much faster.
Cache memory built into the CPU has made data transfer between the processor and RAM far more efficient, allowing significant increases in performance at a reasonable cost.