A

Access time

The time taken to find the location of a specific piece of data or program; this information is used as a measure of the speeds of backing storage devices (such as disk drives).

AI

Artificial intelligence (see machine intelligence).

Algorithm

Animation

The creation of moving images.

Application

The use to which someone puts an IT system.

Applications software

Software used for a specific purpose such as word processing, spreadsheet, database or accounting programs.

ASCII

American Standard Code for Information Interchange; an international coding system for characters.

B

Backing store

Large capacity, permanent memory such as disk, tape or CD-ROM.

Backup

A copy of a program and/or data files.

Bandwidth

The speed of a connection between two computers; bandwidth can be low-band (telephone connections), mid-band (ISDN) and high (fibre optic).

Baud

Unit of discrete signalling speed per second; baud equals bits per second when two state signalling is used.

Benchmark

A standard test used to determine the speed of a component or a system (hardware or software).

Beta

A pre-release version of a program; software companies provide beta programs to beta testers to ensure that the software works before it is released to the general public.

BIOS

A microcomputer’s Basic Input Output System; the BIOS contains basic routines such as the machine’s boot sequence and low level diagnostic routines; the BIOS is normally stored on a ROM.

Bit

An acronym for BInary digiT (0 or 1).

Bit mapped graphics

Electronic graphic file where each minute item (dot) in the graphic picture is represented by a single bit of information in the file. These files cannot be scaled in the same way that vector files can be.

Boilerplating

The use of different sets of standard paragraphs to compose different letters.

Booting

A computer’s automatic start-up routine when it is switched on or reset; the boot program is normally stored on ROM and is responsible for loading the operating system; derived from the saying “picking the system up by its boot-straps”.

Bridge

A device used to connect LANs together.

Broadcast

To send a given signal to a number of receivers or network stations at the same time; messages can be ‘broadcast’ to all stations in a network.

Buffer

A store for data in transfer when two devices work at different speeds.

Byte

A set of bits of standard length normally treated as a unit; usually eight bits which is sufficient to store one character.

C

Cache

High speed memory situated between a processor and memory to store often used data.

CCITT

Consultative Committee of the International Telegraph & Telephone responsible for setting international data communication standards.

CD

Compact disk

CD-ROM

Compact Disk, Read-Only Memory

Client/server

A network system involving one or more central systems (‘servers’) supporting a number of workstations (‘clients’) such as a local-area network system.

Compact disk

A small optical disk, normally 120mm across used to store audio.  When used as a backing storage device to computer systems it is called CD-ROM which can contain audio, text and video.

Compression

The ability to store data in less space than it should occupy without loss of information; this is achieved  using a compression algorithm; ‘data compression’ is not the same as ‘data reduction’ which deletes redundant information (such as audio frequencies humans cannot hear).

Computer based training

Training programmes in which computers (and other IT systems such as interactive video) play a major role.

Configuration

A specific computer set-up in terms of hardware, software and their respective inter-connections, speed, sizes and capacities.

Connectivity

The ability to link computer systems so that they can exchange data.

CPU

Central processing unit; the principal part of a computer system containing processor memory and control units; in a microcomputer system this is called the *microprocessor.

D

DAT

Digital audio tape. Originally designed by Sony and Philips for storing music this media can also store digital data and is commonly used for large-scale backups.

Data

Raw facts and figures before they have been processed (compare with information).

Database

A collection of inter-related data; One or more large structured sets of data, usually associated with software to update and query the data. A simple database might be a single file containing many records, each of which contains the same set of fields where each field is a certain fixed width. A database is one component of a database management system.

Data dictionary

A file which contains the descriptions of all the data items in a database.

Data structure

A means of representing a real-life entity (such as an invoice) inside a computer. Computer programmers create data structures to model real world entities.

Data subject

Someone about whom an IT system holds personal information.

Data user

Someone with access to, or control of, an IT system.

DBMS

Database Management System

Digital

A signal which has discrete states, e.g. on or off; normally represented in binary.

Direct access

The ability to fetch data from media directly without reading the contents from start to finish; this form of access is possible with disk systems.

Documentation

The set of user instructions, background information and notes that come along with hardware or computer programs.

Downsizing

Changing an organisation’s IT systems from mainframe/minicomputer systems to client/server or PC-based systems.

Driver

A program that comes as part of an operating system (or a separate utility program) that controls the working of, and data transfers to, a peripheral (such as a printer or a mouse).

Dumb

A device that has no processing power in its own right (such as a ‘dumb’ terminal connected to a mainframe system).

E

Electronic mail (E-mail)

A messaging facility on a computer network to permit users to transfer information to one another; e-mail systems provide users with unique IDs and provide message creation, storage, forwarding and replying facilities.

Emulation

The use of software to make one system compatible with another; for example, a ‘DOS emulator can permit systems that are not PC-compatible to run MS-DOS programs.

Encryption

Coding data in such a way as to make it unintelligible to unauthorised users for reasons of security.

Ergonomics

The study of how people relate to a particular environment including the impact of hardware, furniture, lighting, heating etc.

Expert system

F

FAT

File allocation table; a means of relating file names with actual locations on a storage medium.

File

A set of organised data in an IT system.

File server

The computer which contains the network software for a LAN and often the applications software accessible by the stations on the network.

Font

The complete set of characters of a given typeface (style, design) in a given size. So 10-point, italics is a particular font of the Helvetica typeface.

Footer

A message giving details of title, author and/or page number which can be set to appear automatically at the bottom of each page of a document.

Foreground

The text or graphics on a screen as opposed to the screen itself which is the background.

Format

The overall layout or shape of anything.

Freeware

Software that incurs no charge to use without limit of time.

G

Gateway

An electronic link between two differently organised networks that allows users of one to access the other.

Generic

Denoting off-the-shelf or not specific; generic software refers to classes of software (such as spreadsheet or graphics).

Gigabyte (Gb)

A thousand million bytes or 1024 megabytes.

Global

Denoting comprehensive, able to apply to a large range of cases or objects; in word processing, ‘global editing’ refers to operations on the entire document.

Graphic

Any pictorial representation of a structure or concept e.g. a line diagram or flow chart.

GUI

Graphical User Interface; the GUI is part of an operating system.

H

Hardware

The physical components of a computer system.

HCI

Human Computer Interface (also known as user interface); the link between an IT system and its users.

Header

A piece of text at the top of each page.

Highway

An alternative term for ‘bus’ or ‘trunk’; a major data path linking a number of devices with the data passing in parallel to increase speed.

Hypermedia

An extension of hypertext to include graphics, sound, video and other kinds of data.

Hypertext

A means of linking related text; specific key words within a text are highlighted and the user can select these keywords and jump to another location within or outwith the document; hypertext is used in the World Wide Web.

I

Icon

A small picture or graphic that represents a program or data item.

ID

Abbreviation for ‘identification’; normally the string used to log onto an information system (such as a network).

Image processing

The application of computers to enhance an image.

Information

The output from an IT system; ‘data’ is input, ‘information’ is output; something that adds to your knowledge.

Information technology (IT)

The handling of information by electronic means including its creation, transfer, processing, storage and access.

Intelligence

A feature of a machine that would be described as intelligence if it was exhibited by a human; an intelligent device has some local processing power (such as a microcomputer on a network).

Interactive

Allowing two way communication (normally between an IT system and a user).

Interface

The physical and/or logical link between two units or systems; in a hardware sense the means of connecting two components.

Internet

The world-wide network; the Internet is a network of networks connected to each other by telecommunication systems; the Internet provides e-mail, file transfer, information retrieval (via the World Wide Web), chat and newsgroups.

IP

Abbreviation for ‘information provider’; a person or group responsible for providing information to an information service.

ISP

Internet Service Provider. A company or organisation that provides users with access to the Internet via their Web server and other internal communication and computer systems. Most ISPs are commercial organisations and charge for providing access to the Internet.

ITU-T

The International Telecommunications Union (formally CCITT) responsible for setting international communication standards.

K

Kilobyte (Kb)

1024 bytes.

Kludge

A jargon term for crude fix to a hardware or software problem.

L

LAN

Local-area network; the connection of intelligent devices within a close geographical region (such as an office or building);  the LAN can be client/server with a specific machine set aside as a file server or peer-to-peer where all work stations are equal and no machine is dedicated to file or print sharing.

Local

Denoting nearby e.g. in the same building or on the same site; a local area network is a network where most of the stations are close together.

Log

A journal or usage report produced automatically by an IT system; to log-in or log-out of a multi-user system is to start or terminate a session.

Low resolution

Crude graphics rather than smooth (high resolution) ones; low resolution graphics involves working with large pixels.

M

Machine

Any single stand-alone unit or system, in particular a computer.

Machine intelligence

Any aspect of a machine’s actions that we would call intelligent if done by a person; the main areas of interest include problem solving, machine learning, knowledge-based systems, machine vision and voice recognition.

Macro

A set of commands that can be executed by an application package in the same way that a batch file can be executed by an operating system.

Mailbox

A data store in an e-mail system for access by one or more people.

Megabyte (Mb)

1024Kb or 1048576 bytes.

Methodology

An organised, documented set of procedures and guidelines for one or more phases of the software life cycle, such as analysis or design.

Microprocessor

A complex integrated circuit (normally a single chip) that carries out the function of a *CPU on a microcomputer system (excluding *RAM).

Millisecond

One thousandth of a second.

MIP

Million instructions per second; a measure of processor speed.

Modem

A hardware link between a digital IT system and an analogue phone line; the name comes from MOdulation/DEModulation - the two main functions of a modem; modems communicate using international communication standards such as V24, V32, V34 etc.

Multimedia

The linking of video, sound, still images and computer generated screens and text.

Multi-tasking

The ability of an operating system to seemingly perform more than one task at a time (such as interrogate an external information service while allowing the user to continue working within a local application package).

Multi-user

Capable of supporting several users; a ‘multi-user system’ is a mainframe or minicomputer system where a single CPU is shared between many users.

N

Netiquette

Network etiquette; the code of conduct that should be followed by computer users especially when working on the Internet. For example, treating all users with respect is an example of network etiquette.

Network

A number of IT units linked by communication channels.  There are two main types - local-area networks (LANs) and wide-area networks (WANs).

Newsgroup

One of Usenet's huge collection of topic groups. Usenet groups can be "unmoderated" (anyone can post) or "moderated" (submissions are automatically directed to a moderator, who edits or filters and then posts the results).  Examples of popular newsgroups are microsoft.public.win2000.general and uk.media.dvd.

Node

A point in a network where channels converge or diverge.

Normalisation

A series of steps followed to obtain a database design that allows for efficient access and storage of data in a relational database. These steps reduce data redundancy and the chances of data becoming inconsistent.

O

Object

An identifiable entity on a computer screen; an object has properties and behaviour.

OEM

Abbreviation for ‘original equipment manufacturer’; any firm that labels original products.

Off-line

Denoting a peripheral or terminal not linked to or needing access to the host system; off-line storage is remote from CPU location.

On-line

Working under the control of, or linked to, a central host system (for example, when logged onto a network). Also used to mean “connected to the Internet”.

Operating system

A set of programs that collectively control the operation of a computer system and provide facilities to the system’s users (such as format diskettes, copy files, compress disk storage etc.).

P

Package

An application package consisting of a program and associated documentation.

PC

Personal Computer; any microcomputer system that is compatible with the IBM-PC.

Peripheral

Any component external to the CPU.

Picosecond

A million of a millionth second or 10^-12 second.

Pixel

An acronym for ‘picture element’, the smallest unit of a screen display the system can address; pixel size effects screen resolution - the greater the screen resolution the smaller the pixels.

Plug compatibility

Hardware components that can be directly attached; a measure of compatibility between hardware devices.

Pointing device

An input device used to control the cursor such as a mouse or a light pen.

Polling

Interrogating peripherals in turn to check their status and to avoid clashes.

Port

A connection for an interface on a computer system such as a ‘printer port’.

POST

Power On Self Test; the routine that a system goes through when it starts up.

Portability

A measure of the ease with which a program can be transferred from one machine to another.

Processor

The central part of an IT system (see CPU).

Program

A set of instructions to accomplish a specific task; programs are written using a programming language.

Proprietary

Denoting copyright i.e. owned by someone.

Protocol

A set of rules, formats and procedures for using a communication system; some protocols have become internationally accepted to permit communications between countries.

Q

QWERTY

The standard keyboard layout named after the sequence of letters on the top row of alphabetic keys.

R

RAM

Random access memory.

Random access

A common term for direct access to data; disk is a random access storage medium; tape is a sequential access medium.

Real-time

Describing a system that reacts at once to its inputs (such as most process control systems where reaction to inputs must be instantaneous).

Recovery

A process whereby a system restarts normal working after some major failure.

Remote access

Access to a computer system at a distance from the terminal or work station in question (normally involving telecommunications).

Resident software

Routines built into an a computer that are permanent available; these programs are stored on non-volatile medium such as ROM.

Response time

The time taken to respond to an event such as the pressing of the <RETURN> key.

RISC

Reduced Instruction Set Computer; a machine with fewer native instructions that is meant to run faster than CISC (Complex Instruction Set Computer) machines.

ROM

Read Only Memory; a semiconductor memory whose contents are fixed at manufacture; a microcomputer’s BIOS is normally stored on ROM.

S

Semiconductor

A substance that conducts electrical current to a small extent (more than an insulator - such as rubber - but less well than a conductor - such as metal); silicon (derived from sand) is a semi-conductor found in computer systems.

Sequential access

Access to data in the order that the data is stored; compare with random access.

Shareware

Software that is initially free to use but requires to be purchased if used beyond a specified time period (see ‘freeware’).

Shell

User interface software; a program that sits between the operating system and the user.

Simulation

Computer software that models some real life activity; pilots use aeroplane simulation systems to learn to fly planes.

Software

A term for a computer program together with its associated documentation; there are two types - systems software (operating systems, utilities etc.) and applications software (packages).

Snail-mail

The traditional postal service.

Spike

A sudden brief voltage peak in an electric circuit that can cause the loss of information.

T

TCP/IP

Transmission Control Protocol over Internet Protocol. The standard protocol used for connecting computers to the Internet.

Teleworking

Working from outside of the main workplace, often from home. A ‘teleworker’ requires access to communication and computer equipment and communicates with the workplace through e-mail and the Internet (or a private network).

Telecommunications

A system that uses telephone lines, cables or satellite to transmit and retrieve information.

Terminal

An access point to a multi-user or network system that has little or no local intelligence.

Topology

The layout of a computer network; common topologies include the star, bus and ring layouts.

Throughput

A jargon term to denote the rate of data transfer through an IT system from input to output.

U

User interface

The means by which a user interacts with a computer system; modern computers use a graphical user interface (GUI).

UPS

Uninterruptible power supply; a power supply that is independent of the national grid that permits IT systems to remain active during a power failure; UPS are required for safety critical systems; UPS only cut in when the normal supply fails.

Upsizing

Upgrading an IT system to improve its performance (such as PC-based system being upgraded to a client/server system).

URL

Uniform Resource Locator; a unique address that is used to identify resources (pages) on the World Wide Web (for example http://www.sqa.org.uk).

User

Anyone who accesses an IT system.

Utility

A small program designed to carry out some maintenance task; utility programs normally compliment the operating system’s suite of programs.

V

Validity check

A test, normally conducted by a database system, to ensure the accuracy of data whereby input is checked against a range of acceptable values. For example, a validity check for a person’s age would check that it lies between sensible values (say 0 to 100).

VDU

A term for screen and keyboard.

Vector graphics

A drawing program which deals with separate shapes such as lines, polygons and text and groups of such objects as opposed to a painting program which stores only bitmaps. The advantage is that it is possible to change any element of the picture at any time since each part is stored as an independent object whereas once something in a bitmap has been overwritten it cannot in general be retrieved.

Virtual reality

The use of an IT system to feed the user’s senses with stimuli that model real world conditions and thereby give the impression of moving within a virtual world.

Virus

A hidden program that can change the contents of another program and cause a computer system to malfunction; computer viruses spread from disk to disk by copying infected programs.

V24

An international communication standard for devices that communicate at a speed of 2,400bps.

V32

An international communication standard for devices that communicate at a speed of 9,600bps; V32bis communicates at a speed of 14,400bps

V34

An international communication standard for devices that communicate at a speed of 28,800bps.

V42

A data compression standard.

W, X, Y, Z

Wide-area network

A network of IT systems spread over a large geographical area often require telecommunication systems to connect nodes.

WIMP

Windows, Icons, Menus and Pointers; a type of user interface.

Window

A portion of the screen that stores its own data and can act independently of the rest of the screen.

World Wide Web (WWW)

A huge hypermedia database consisting of millions of pages of information interlinked by hypertext. Each pages on the Web has a unique URL.

WYSIWYG

What-you-see-is-what-you-get; an acronym to describe a *program that presents on the screen an accurate representation of what will be printed on paper.