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Flashcards in Keywords Deck (111):
1

Abstraction

Definition: The process of removing or hiding unnecessary detail so that only the important points remain.

2

Binary

Definition: Information represented by only two values (e.g. a voltage or no voltage, on or off).

3

Entity

Definition: Something that is recognised as being capable of an independent existence is uniquely identified and about which data is stored.

4

Boolean

Definition: Something that can take only the values true or false; named after English mathematician George Boole.
This operator just swaps 1s and 0s.

5

Integrated Development Environment

Definition: A package that helps programmers to develop program code. It develop program codes. It has a number of useful tools, including a source code editor and a debugger.

6

Digital

Definition: Information represented by certain fixed values. (E.g. high, medium or low.) Any signal between these values would be meaningless and not used. Sending and receiving mechanisms do not have to be as accurate as for analogue communication.

7

Analogue

Definition: Using signals or information represented by a quantity (e.g. and electric voltage or current) that is continuously variable. Changes in the information being represented are indicated by changes in voltage.

8

Byte

Definition: The basic combination of bits used to represent an item of information. A byte typically consists of 8 bits.

9

Integer

Definition: A whole number (e.g3, 6, 9).

10

Binary Shift

Definition: An operation done on all the bits of a binary value in which a specific number of moves them placed to either the left or right.

11

RSI
(Repetitive strain injury)

Definition: Damage caused to the muscles, tendons, ligaments, nerves or joints, usually because of repeating the same action.
Examples: Typing or using the mouse for extended periods. Using a poorly designed keyboard.

12

Etiquette

Definition: A set of rules that people try to abide by out of respect for other people around them.
Examples: Using the correct format in writing an e-mail for example capital letters in the proper place, correct spelling and punctuation.

13

Public Domain

Definition: Materials that are available for anyone to use for any purpose (not subject to laws of copyright)
Examples: Any software written before 1974 is public domain. The works of Shakespeare and Beethoven.

14

Primary Storage

Definition: Built-in storage designed to be directly accessed by the central processing unit (CPU).
Examples: Random Access Memory (RAM) and cache are both examples of a primary storage device.

15

Hexadecimal

Definition: A based-16 number system. There are 16 digits and the place values increase in power of 16.

16

Character Set

Definition: The defined list of character recognised by a computer’s hardware and software.

17

Input

Definition: To enter data in to a computer.

18

Process

Definition: To change the meaning or format of some data.

19

Output

Definition: To display or output data that has been processed (or has been stored).

20

Software

Definition: Programs that give instructions to a computer and which allow the user to carry out different tasks.

21

Von Neumann architecture

Definition: Computer system design in which the program is stored in memory with the data.

22

Central processing unit

Definition: Hardware device that carries out the processing in a computer.

23

Main memory/Ram

Definition: A temporary store for a data and instruction (programs).

24

BUS

Definition: A group of connections between devices in a computer.

25

Fetch-decode-execute cycle

Definition: Sequence of steps carried out repeatedly by a CPU.

26

Latency

Definition: The time delay between the moment something is initiated and the moment it becomes detectable.

27

ISP
(Internet Service Provider)

Definition: A company that provides Internet access to its customers.

28

Writing

Definition: When the CPU sends data to the memory to be stored at a given address.

29

Reading

Definition: When the CPU retrieves the data stored at a given address.

30

Volatile

Definition: Memory that is erased when the power is turned off.

31

Non-Volatile

Definition: Memory that is not lost when the power is off.

32


Read-only memory (ROM)

Definition: Memory that cannot be altered and is not lost when the power is turned off.

33

Cache

Definition: Memory used to make up for the difference in speed between two internal components.

34

Clock

Definition: An electronic device inside a CPU that ‘ticks’ at regular intervals and is used to synchronise the action of the other part of the CPU.

35

Bus width

Definition: The number of wire that make up a bus-this determines the range of binary numbers that can be transmitted.

36

Magnetic storage

Definition: Any kind of permanent storage to which the contents of ROM/RAM are copied (usually a hard disk, optical or solid-state device).

37

Optical storage

Definition: Secondary storage that works by magnetising parts of a substance as north and south poles to represent binary 1s and 0s

38

Solid-state storage

Definition: Secondary storage that works by storing charge (electrons)

39

Plagiarism

Definition: Copying someone else’s work and presenting it as your own.

40

Virus

Definition: A program designed to cause a computer to malfunction or stop working altogether.

41

Fraud

Definition: Tricking someone for personal gain or to damage them.

42

Virtualisation

Definition: Any process that hides the true physical nature of a computing resource, making it look different, usually to simplify the way it is accessed.

43

Hacker

Definition: Someone who gains unauthorised access to a computer in order to obtain data stored on it.

44

Identity Theft

Definition: A crime that involves someone pretending to be another person in order to steal money or obtain other benefits.

45

Truth table

Definition: A table showing all possible combinations of the input and output of an operator.

46

Logic Circuit/Gate

Definition: An electronic circuit that has inputs and outputs that follow one of the Boolean operators.

47

Operator precedence

Definition: The order in which you apply the operators (including logical operators in a mathematical equation.

48

Scheduling

Definition: The algorithm that runs the OS uses to allow each running process to use the CPU.

49

Paging

Definition: The algorithm the OS uses to move programs from RAM to disk and back again when needed once main memory is full.

50

Concurrent

Definition: Processes that run apparently at the same time are described as being concurrent.

51

USB
(Universal Serial Bus)


Definition: A standard method of connecting devices such as keyboards and printers to a computer.

52

Authentication

Definition: The process of proving to a computer system who you are (e.g. using a username and password).

53

User interface


Definition: The way the user interacts with the operating system.

54

Defragmentation

Definition: A utility that moves file clusters on a disk so they are closer to each other in order to speed up disk access.

55

Cloud Computing

Definition: A system in which all computer programs and data is stored on a central server.

56

‘What if? Question

Definition: Running a computer model with a give set of input to see what the model produces as an output or prediction.

57

Heuristic

Definition: A type of algorithm capable of finding a solution to a problem quickly and easily, by using combination of trial and error and educated guesswork to cut corners and eliminate less likely alternatives. Heuristic algorithms don’t always find the best soone lution but they will usually find that works.

58

Monte Carlo methods

Definition: Carrying out a statistical analysis of a number of random sample in order to obtain approximate solutions to a problem. The larger the number of samples used, the more accurate the results us likely to be.

59

Neural networks

Definition: Processing information in a similar way to human brains, learning, and adapting over time. This makes them useful tools for solving pattern recognition medical diagnosis and quality control, which computers are normally not very good at.

60

Instruction set

Definition: The list of all possible commands a particular CPU knows how to carry out

61

Translator

Definition: A program that converts source code into machine code.

62

Pixel

Definition: Short for “Picture element”, the smallest single point of colour in graphic image.

63

Resolution

Definition: The number of pixels per inch when the image is displayed (for example, on a monitor or on paper.

64

TB
Terabyte

Definition: Terabyte or 1000 gigabyte.

65

Sampling

Definition: Taking measurements of the sound wave at regular but distinct intervals of time (e.g. 44.100 samples per second).

66

Machine code

Definition: The binary code representing each of the instruction in the instruction set.

67

Assembly language

Definition: A low-level language written using mnemonics.

68

Phishing

Definition: A form of internet fraud that aims to steal valuable information such as usernames and passwords.

69

Low-level programming language

Definition: A programing language that is closely related to the CPU’s machine code

70

Mnemonic

Definition: A short, simple, acronym that represents each of the instructions in a CPU’s instruction set, E.G. LDR (Load register), STR (store) and CMP (compare).

71

Compiler

Definition: A translator that converts high-level language source code into object code, often machine code. The source code is translated all at once and saved to be executed later.

72

Interpreter

Definition: A translator that converts high-level language source code into object code, often machine code. The source code is translated and executed on line at a time.

73

Bandwidth

Definition: The amount of data that can fir through an Internet connection. Bandwidth is measured in bits per second (bps).

74

Object code

Definition: The translated source code. Often this will be machine code, but might also be an intermediate code, which has to be further translated before it can be execute

75

Firewall

Definition: A system designed to prevent unauthorised access to your computer when connected to a network.

76

Spyware

Definition: Software that can be installed on your computer without your knowledge, which collects personal and private information.

77

Network

Definition: An arrangement of computers and other devices connected together to share resources and data

78

Local area network (LAN)

Definition: A local area network that covers a relatively small geographical area, often a single site.

79

Wireless local area network (WLAN)

Definition: A local area network in which connected devices use high frequency radio waves to communicate.

80

Wide area network (WAN)

Definition: A network that covers a large geographical area. It connects together two or more LANs and is usually under collective ownership. The largest wide area network is the internet.

81

Client-server network

Definition: A network that has at least on server to provide services to the client computers.

82

Encryption

Definition: For security, data is translated into a secret code according to a set of rules in a special “key”.

83

Peer-to-peer network

Definition: A network that does not have any centralised servers. Each computer in the network can act as client and server.

84

Copyright

Definition: Gives the creator of an original work exclusive rights regarding that work for a certain period of time.

85

Network topology

Definition: Describes how the devices on a network are connected together.

86

Malware

Definition: Software that is designed to cause problems for users.

87

Internet

Definition: A worldwide system of interconnected networks that enables information to be exchanged and shared.

88

Dongle

Definition: A small piece of hardware that connects to a computer and has uses including data storage and picking up Bluetooth and 3G signals.

89

Communication media

Definition: The means by which data is transmitted between devices on a network. Coaxial cable, fibre-optic cable and microwaves are all forms of communication media

90

Protocol

Definition: A set of rules that govern how communications on a network should be formatted and what data they should include.

91

Eavesdrop

Definition: Having unauthorised sight of data being sent from on computer to another over a network. This is covered more fully in the later section on technical weakness.

92

Checksum

Definition: An error detection technique. A mathematical formula is applied to the data and resulting numerical value is transmitted with the data. The recipient computer applies the same formula to the received data and then compares the checksum sent with the data to calculated checksum. If the checksum do not match, the data is likely to have been corrupted and the recipient computer request the data again.

93

Packet

Definition: A small quantity of data being sent thought a network. The packet is labelled with the sender’s address (source), the recipient’s address (destination), how many packets are being transmitted and the position of this packet in the complete message.

94

Web server

Definition: Powerful computer system that store web pages and any multimedia that the pages might contain.

95

Network security

Definition: Activities designed to protect a network and its data from threats such as viruses, hacker’s attack, denial of serve attacks, data interception and theft, and equipment

96

Backup

Definition: A copy of data that is made in case the original data is lost or damaged. The backup can be used to restore the original.

97

Secondary storage

Definition: Storing data on another device, such as a CD or USB pen.

98

Denial of service (DoS)

Definition: An attack on a network that attempts to prevent legitimate users from accessing its services.

99

Access control

Definition: This determines which users have access to which data, and what they are allowed to do with it

100

Physical security

Definition: Controlling access to critical parts of a network using physical methods (such as locked doors) rather than software

101

Cyberattack

Definition: Any kind of malicious attack on a network- connect device

102

Shoulder surfing

Definition: Gaining access to information by watching someone enter it into a computer system

103

Unpatched software

Definition: Software that has not had the latest security updates applied to it, making it vulnerable to attack.

104

Code vulnerability

Definition: A computer program (the code) that has been written in such a way that it creates a security issue that may be taken advantage of to gain access to the computer system or data within it.

105

Modular testing

Definition: Testing each block of code as it is completed to ensure the code works as expected.

106

Audit trail

Definition: A record of activities that have taken place on a computer system. This record is generated automatically and will record what has happened and who or what made the change.

107

Internet Service Provider (ISP)

Definition: An organisation that provides its customers with a connection to the internet.

108

Router

Definition: A piece of networking hardware used to forward packets of data from one network to another.

109

HyperText Markup Language

Definition: Essentially text documents that contains any text to be displayed along with:
Detail of how the text should be formatted (e.g. font size, colour etec.):
Details of any hyperlinks and where the links to using a URL;

110

Computing technology

Definition: An all-encompassing term referring to the hardware, software and infrastructure that underpin current and emerging computer system.

111

E-waste

Definition: Any form of discarded electronic equipment including computing technology.