A Glossary of Computer and Communications Jargon

To reach, connect or interact with a remote resource.
A unique alphanumeric sequence used to identify a computer transmitting or receiving data. Also a location in memory.
The use of continuously changing quantities to represent numbers.
Software which does productive external work, as opposed to system software which is internal to the computer system.
Broadband ISDN - a more technical way of describing the information superhighway.
High speed communications channel connecting networks, often using optical fibre.
Measure of the capacity of a communications channel. Used to indicate the amount of information available on a channel, and sometimes, confusingly, its speed.
Communications channels which carry data without modulation and are therefore slower and less capacious than broadband, although probably more reliable. Typically used for local area networks.
Baud, baud-rate
Named after 19th century French engineer J.M.E. Baudot and much used in telegraphy, the baud-rate is the number of characters a second sent down a single communications channel. 1 baud=1 character per second. When the channel is transmitting bits, one baud equals one bit per second. Bauds are used to measure the speed of a communications channel.
Bit(s), bit(s) per second (bps)
Short for Binary digIT. The basic unit of information, represented as an entity in one of two possible states: on or off, high or low, zero or one. Electronic switches, trains of electrical pulses, and binary numbers (eg 10011011) can all be used to represent groups of bits. A sequence of bits is called a bit stream, and the speed of a communications channel in a serial connection (bit-rate) is given in bits per second.
Hardware used to connect similar networks.
Communications channels which use modulated carrier signals for data, like radio waves, and are therefore faster and more capacious than baseband (ie. they have a higher bandwidth). Examples are satellite and fibre optic cable systems.
A group of eight bits used to represent a single digit (eg. 7), letter (eg. N), or symbol (eg. +). The unit of memory on a PC. 1 Kilobyte = 1024 Bytes, 1 Megabyte = 1024 Kilobytes, 1 Gigabyte = 1024 Megabytes.
International consultative committee for telephony and telegraphy. See ITU.
Compact disk/Read-only memory. A compact disk used to carry data rather than, or as well as, audio in permanent memory. CD-ROMs can store up to 660 Megabytes of data, making them useful for large databases or multimedia applications.
A unidirectional route for communication - two channels (input and output) form a circuit. Also a link to a host computer.
Circuit switching
A form of data communication which establishes a single connection or circuit between source and destination to carry the data stream. Like a conventional telephone system.
The ability to connect computer or communications systems to exchange data or share resources.
Literally, "that which is given", data refers to raw facts, measurements, numbers, and so on. Data can exist in any form, but is commonly identified with electronic digital signals.
Organized files containing information of the same type. Data communications: Transmission and reception of data on networks.
Data superhighway
Phrase coined by the then Senator Al Gore in connection with his National Information Infrastructure (NII) white paper, 1993. The NII is a proposed high speed national data communications network capable of carrying interactive multimedia in real time, faster than current LAN technology. By analogy to road highways, the NII will supposedly carry the raw materials, fuel and produce of future knowledge-based industries.
A computer small enough to sit on a desk top. Also used to refer to the graphical representation of an office environment (with card index, waste bin, filing cabinet, and so on) that is a feature of GUIs.
Method of accessing on-line services using ordinary telephone connections.
Using numbers to represent quantities or symbols. An electronic digital signal consists of discrete, countable pulses of fixed size.
There are various forms of disk (US spelling) used to store files for use with computers. They are usually classified by physical size (eg. 3.5 inches), storage capacity (eg. 210 megabytes), and physical medium (eg. magnetic, optical, magneto-optical).
Using smaller, cheaper computer or communications systems to do the same job - and employing fewer workers.
Electronic mail. Human-readable messages sent between computers. When used as a verb, to send such messages.
Electronic data interchange. A form of e-mail in which the allowable types and structures of message are formally defined and are usually connected with trading. EDI messages are, for example, invoices, delivery notes, bills of lading, and remittance advice.
End user
The person who makes productive use of the information produced by an information system.
Fibre optics
The use of optical fibre for communications.
Data which has been organized, stored and named. In computing, files are usually stored on disks.
GII, Global Information Infrastructure
The policies and technologies associated with the coordinated development of linked international digital networks. An extension of the NII or data superhighway idea.
See the Internet.
Software designed to help teams or groups of people work together. Invariably includes e-mail.
GUI (pronounced "gooey"), Graphical user interface
Software designed to make applications easier to use by giving them all the same look and feel, usually involving a `mouse' to move a pointer on the computer screen, menus to select actions, and a variety of `buttons' or `sliders' (collectively known as "widgets") which can be used to perform tasks or manipulate the screen.
Equipment. The electronic, electrical and mechanical components of information systems.
A central computer which provides services, such as database access, to users across a network. Also known as a server.
Integrated broadband communications. Another way of talking about information superhighways. Term used by European Commission.
Information and communications technology (see IT&T and telematics). Commonly used as a European industrial classification.
The European version of a data superhighway.
Organized data which is understood to have significance and meaning.
Information infrastructure
A physical communications network, particularly of national or global scope.
Information society
A society in which economic and cultural life is critically dependent on information and communications technologies. Popularised in Europe by the 1994 Bangemann report on 'Europe and the global information society'. Similar to the NII and GII concepts but focusing less on technology, more on uses.
Information superhighway
A media expression for the policies and technologies associated with the development of high speed national and international data communications networks.
Information systems (IS)
Computer and communications hardware and software used to supply information rather than, for example, control machines. Often used interchangeably with information technology.
Information technology (IT)
Computer and communications hardware and software used to automate and augment clerical, administrative, and management tasks in organizations.
The characteristic of systems which accept user input as well as delivering output. Distinguishes, for example, conventional TV or video from multimedia or videoconferencing.
The ability to link hardware, typically from different manufacturers, so that it can communicate.
The Internet
An intercontinental network of networks originally based on military and academic systems but increasingly used for commercial and private communications. Also a standard for addressing e-mail messages on this network, favoured by the US (see X.400 ). Gopher, WAIS and WWW are applications used to retrieve information from computers on the Internet
Linking networks to make a bigger network.
Interoperability, interworking
The ability to link systems so that they can actually work together like one, big system.
Integrated services digital network. Digital telephone systems capable of transmitting data much more quickly than conventional analogue systems and without the need for modems.
International Standardisation Organization. A United Nations body with responsibility for international technical standards, except those covered by the CCITT.
Information technology and telecommunications. Commonly used as an industrial classification.
The International Telecommunications Union, formed in 1865. Now part of the UN. Coordinates standards activity through the CCITT, and implements internationally agreed policy..
UK academic network, now being superseded by a faster network called SuperJanet.
Organized or contextualised information which can be used to produce new meanings and generate new data.
LAN, Local area network
A medium-to-high speed network restricted to a room, floor or building. LANs which run between a few neighbouring buildings are often called campus networks.
PSTN line reserved for private data communications. Used in low-to-medium speed WANs. In UK supplied under trade names such as Kilostream and Megastream.
To disconnect from a network in the prescribed manner.
Log-on (also, log-in)
To connect to a network and identify yourself.
A large, expensive, powerful central computer. Called a mainframe because early computers occupied a number of metal frames, the main one of which contained the processor and memory.
MAN, Metropolitan area network
A PTT controlled, low-to-medium speed network linking sites within a town or city.
Electronic circuits which store data, permanently (Read Only Memory/ROM) or as long as they have power (Random Access Memory/RAM).
Very small computer (typically a PC) designed around a microprocessor - a processor on a single silicon chip.
A smaller computer than a mainframe, designed originally for use in laboratories and containing everything in one box.
Short for MOdulator-DEModulator. A device which modulates an analogue signal with a digital signal for transmission down a conventional telephone line, recovering the digital signal at the other end.
Modulate, modulation
The effect of superimposing a slowly changing electrical signal onto a much faster carrier signal, so that the faster signal can be used to convey information. Central to radio.
The presentation of information or entertainment by a combination of data, images and sounds. Can be delivered in a variety of ways - on a computer disk, through modified televisions, or using a computer connected to a telecommunications channel.
A collection of linked computers which can exchange data, share resources, or even make use of each other's software. Networks allow people to communicate, and work cooperatively. They also make it easy to monitor and control work at one computer from another, remote computer. They are commonly classified as Local Area Networks (LAN), Wide Area Networks (WAN), or occasionally Metropolitan Area Networks (MAN).
National information infrastructure, see data superhighway.
To be actively connected to a network, usually a WAN, or a remote computer. On-line databases are databases stored on remote computer systems accessible across a network.
Optical fibre
Translucent fibre which can transmit beams of laser light. Used for reliable high speed LANs and backbones.
Contracting out some or all of an organization's IT or communications operations. Often believed (erroneously, according to recent research) to lead to cost savings.
Packet switching
A form of data communications which breaks a data stream into small sections, sends them separately by the best available channels and reassembles the original data stream at its destination.
Parallel connection
A link between systems or resources in which several channels are active at the same time carrying several bit streams.
A code which authorises access to protected networks, systems or files.
Personal computer. A small computer of limited capacity capable of performing basic IT functions like word processing. Can be networked to other computers and system resources.
Plain old telephone services. Analogue telephone system.
Component of a computer system which manipulates data.
Public switched telephone network. Public telephone system.
Public telephone authority or administration.
Public telephone operator.
Post, telegraph and telephone administration.
Public packet network
Public X.25 networks like BT's Packet Switch Stream (Dialplus) or France Telecom's Transpac.
Real time
Refers to applications which perform tasks without delay.
System components which can be used by the central processor, particularly, storage, memory, and input/output channels and devices like printers; also associated files and software.
Installing supposedly cost-effective computer or communications systems, but often used as a more neutral way of talking about downsizing.
Specialised computer used to link dissimilar networks.
Serial connection
A link between systems or resources in which only one channel is active at one time carrying a single bit stream.
Computer programs (note the US spelling). Component of information systems comprising instructions for hardware. Sometimes this is understood to refer to the programs and the physical media on which they are supplied.
E-mail systems which use a central computer to store messages until the recipient wishes to retrieve them.
Set of connected and mutually interacting components.
Telecommunications company.
The transmission and reception of information-bearing electrical signals between remote systems.
The convergence of computing and communications technologies, thus the use of telephone or radio to link computers and the use of computers to send messages via telephone or radio links. A term commonly used in Europe, particularly by the European Commission.
Non-interactive data communications using spare capacity in television channels. For example, Oracle and Ceefax.
The use of telematics to allow people to work away from offices or factories. Work rate can be remotely monitored.
Anyone using an IT or telecommunications system.
Video on demand
Multimedia product (as yet only experimental) in which individually requested videos or movies will be delivered in digital form to viewers down their telephone lines.
Interactive communication using video and sound transmitted over telephone lines in real time. A form of multimedia and a common application for ISDN.
Generic term for low speed interactive information services using PSTN and computer-type terminals - for example, Prestel in the UK, minitel in France. Also known as Viewdata. Often used for simple data communications applications in travel agents, banks and so on.
WAIS (pronounced "ways")
See the Internet.
WAN, Wide area network
A network connecting sites separated by large distances, typically using backbones. In the past. slower than LANs but used to communicate between them.
A GUI for PCs produced by Microsoft.
Applications for networked computer systems which use the metaphor of a production line to model, manage and monitor clerical, administrative, and document-based tasks.
A team of people engaged in a cooperative task. Workgroup computing uses groupware to assist in this task.
A powerful PC often used for scientific applications. Also a desk, chair and other equipment at which someone works.
WWW, World Wide Web (also known as The Web)
See the Internet.
A CCITT standard for low-speed packet switching used as a lower cost alternative to leased-lines in many WANs.
An e-mail addressing standard formulated by the CCITT, and supported by most European PTTs.

Top of page

Copyright This glossary is copyright Gary Herman and was first published in September 1994 by the Labour Telematics Centre, a national project of the Workers Educational Association providing services for the trade union and labour movement. It can be reproduced freely in any form as long as it is reproduced in its entirety and this notice is included.

The LTC can be contacted by phone on +44 (0) 161 860 4364, fax on +44 (0) 161 862 9512, or by e-mail at

Glossary of Internet Terms


[Home] [E-mail]

Designed and Hosted by