[page 50]
Glossary/index of specialist terms
The numbers shown refer to pages.
Algorithm: a sequence of operations describing a solution to a problem in a finite number of steps. See also Programming
Analogue: an analogue measurement represents a quantity by displaying a continuous signal. For example a quantity of electricity used may be represented by the turning of a dial. See also Data representation
Animation: a sequence of images which are rapidly superimposed one on another to produce the impression of movement.
animated strip 15
Application: the use of the computer to solve specific user tasks in the processing of data. An applications package is a set of specialised programs and associated documentation to carry out a particular application, such as the control of a company's stock.
computer applications 37-38
desk-top publishing 3,8
simulations 4, 6, 13-14, 25-27, 41, 46-48
spreadsheets 3, 12, 23-26, 40-44
statistics packages 26
synthetic speech 7, 30
word processing 3, 8, 19, 22
Bar code: a pattern of lines of different thicknesses giving coded information about the item to which it relates, such as an ISBN book number.
bar code reader 1
bar coding 18
BASIC: See Computer language
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Calculator: a device designed to manipulate and display numerical data. Sophisticated electronic calculators can be programmed for specific applications and may be able to display results in a graphical form or as algebraic expressions.
calculator 1, 3, 14, 26-27, 46-47
electronic calculator 14
numerical, algebraic, graphical and programmable 47
CD-ROM: a device for storing large quantities of data using a compact disc similar to those used for recording music in a digital form. ROM stands for 'read only memory', i.e. the data stored is fixed and can be read, but not changed.
Central processing unit: the main part of the computer which processes instructions and controls the operation of the computer system. See also Computer, Hardware
Computer: an electrical machine which can both process and store information; the information may consist of numbers, words, symbols or images or any combination of these. A computer accepts information using an input unit. The information is processed by a central processing unit and the results are supplied by an output unit. A computer is controlled by means of instructions given in the form of a program.
computer-aided drawing and design (CAD) 28,45
computer-aided learning package 41
computer application 37-38
computer club 43
computer-controlled lathe 25
computer database 12,23
computer language 47
computer models 26, 27
computer program or procedure 25-27, 46-47
computer software 3,5
computer studies/computing 2, 4, 33, 37, 39-44
computer system 34, 39
computer thesaurus 10, 35
computerised toys, games and calculators 1
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Computer-aided drawing and design (CAD): the use of a computer in producing drawings and designs for industrial, engineering, aesthetic or scientific purposes. Drawings, produced on the screen, are stored in the computer and can be manipulated to produce a design in a variety of perspectives and with special effects. See also Application, Computer
Computer control: the use of a computer to control machinery or to monitor a given environment and respond appropriately to any changes which may occur. For example, if both the input and output units are connected to a manufacturing process, outputs from the process may be used as input to the computer, which can then be used to control the process.
Computer language: a defined set of characters and symbols which may be combined by specific rules to produce an artificial language for communicating instructions to programmable machines. See also Programming
Computer system: a central processing unit together with its input and output devices and any software required. See also Computer, Hardware, Software
Data: any group of facts, numbers or symbols which describe a state, a value or a condition. Data usually describes a fact or an event; it is contrasted with information which is conveyed by a set of data, and with a computer program which is a set of instructions operating on data.
data 6, 11-13, 18, 27, 31, 35, 38-40, 45-49
data capture 3, 10, 13, 15, 24, 28
data from sensors 30
data protection 46
remotely sensed data 39
validity 23-25
Data-logging: the use of a device to capture data and record it immediately so that the data may be processed at a later date.
data-logging equipment 30
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Data representation: the way in which data is held and organised in a computer. The majority of computers represent data internally in digital form. Data from the environment, such as sound waves from a speaker, is often received in analogue form. For the computer to represent and respond to many real events, it is therefore necessary to be able to convert data from analogue to digital and vice versa.
analogue 30
digital 30, 46
digital meter 46
Database: a collection of structured data where the structure of the data is independent of any particular application. Databases are created, updated and accessed by special software called a database management system.
database software 12
databases 3, 6, 23-24, 31, 33, 40-43, 45-49
national database 12
Desk-top publishing: a computer applications package which facilitates the integration and production of text and graphics within a document. See also Application
Digital: a digital measurement represents a quantity, such as time, by displaying a discrete signal which changes by steps. In a digital computer, data is represented by combinations of discrete states usually symbolised by 0 and 1. See also Calculator, Data representation
Electronic mail: the sending of written messages, from one computer to another, by telephone. Messages are stored in a central computer system to be retrieved when the recipient subsequently communicates with the central computer by telephone. See also Text handling
Firmware: See Software
Floor turtles: an electro-mechanical device, controlled by LOGO or another computer language, for executing movements, drawing designs, and activating sound or light effects. See also Programming
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Graphics: the representation of information by the computer in graphical form. The display may be as charts, diagrams, pictures or animations. Special devices are required to produce paper copies of graphical data.
graph plotters 26
graphics software 4
Hardware: the name given to the physical components of a computer system. It includes both the logic circuit and logic gates forming the central processing unit and other peripheral devices, such as keyboards, screens and printers, which are connected to it.
automatic device 1, 4, 46-47
computer-controlled lathe 25
computer system 34, 39
hardware 4-6, 9-10, 39-40
interface 17,29
keyboard (including overlay) 10-11, 16, 24, 45
logic circuit 6,46
modem 22
mouse 48
peripherals 39
pressure pads 17
radio alarm 46
sensor 17, 30, 35, 48
synthesisers 4, 15,28
telecommunications link 6, 12
touch screen 29
Information: a collection of items, such as text, data, symbols, images or sounds which conveys meaning.
information 1-4, 6-7, 11-13, 21-27, 31-34, 37-39, 42, 46-49
information systems 37
information technology 1, 43, 45
Information technology: the application of appropriate technologies to the processing of information. In general, this currently refers to the use of computing, telecommunications and digital electronics. See Information and p.1
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Input unit: a device, such as a keyboard, that puts data or instructions into a computer. It allows people to communicate with computers and may accept either coded information or human readable information such as magnetic ink or optical characters. See also Computer
Interface: the hardware and associated software needed between processors and peripheral devices, to compensate for the differences in their operating characteristics. See also Hardware
Logic circuit: an electronic circuit made from a combination of logic gates to perform a particular logical operation.
Logic gate: an electronic switch which may have more than one input, but only one output. The output is activated when a given set of input conditions are met.
LOGO: See Computer language
Modem: a device capable of transforming computer data so that it may be transmitted or received via a telephone line or radio link.
Mouse: an input device which the user moves around a flat surface in order to select the required response from a computer system, e.g. to move a cursor around the screen.
Output unit: a device that receives data from a central processor which it either stores or outputs in human readable form, such as a printer or graph plotter. See also Computer
PASCAL: See Computer language
Peripheral: the term used to described input, output, or other devices which can be connected to a central processing unit.
Program: a set of instructions in a computer language for executing an algorithm.
Programmable item: any device that stores a sequence of instructions which are carried out automatically, such as a cooker, toy, or calculator. See also Calculator, Software
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Programming: the process of producing a finite set of rules, or algorithm, giving a sequence of operations for solving a specific problem. The final step requires writing, or coding, the algorithm in a form which the computer can understand and the process includes testing to ensure that the results produced are correct.
algorithm 16, 26
assembly code 40
BASIC language 40
coding 18, 26, 40
computer language 45
computer software 3, 5
interpreters 26
LOGO language 39-40
microcomputer program 46
PASCAL language 40
programmable toys and floor turtles 16
tool-box 40
Remotely sensed data: data associated with information, such as the height of a river, which is collected by sensors positioned either on site or remotely and transmitted electronically. See also Data
Sensor: a device with an input which measures some external phenomenon quantitatively and an output which can be read by a computer, for example, a thermometer which produces a digital output. See also Hardware
Simulation: the use of a computer to process a model of a real or imaginary system. Simulations may be used to study the behaviour of systems which would be difficult, impossible or dangerous to reproduce in the classroom.
adventure game 13-14
computer models 26-27
computer simulation 43
simulations 4, 6, 13-14, 25-27, 41, 46-49
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Software: the programs, routines, procedures and packages together with their associated documentation which can be implemented on a computer system. Some of the software may be permanently installed on 'read only memory' within the computer and this is known as firmware.
computer system 34, 39
firmware 39
Spreadsheet: a computer applications package which allows the user to record, structure and manipulate numerical data easily. See also Application
Synthetic speech: the simulation of human speech by hardware and software within a computer system.
Teletext: a computer-based information retrieval system which uses screens of text and simple graphics. The information is displayed in pages and may be broadcast by television or via the telephone. Viewdata is the general term for interactive systems such as PRESTEL, where information may be transmitted as well as received.
teletext 1, 24, 46
teletext format 11
teletext in the home 47
viewdata systems 3, 47
Text handling: the processing to textual material. It includes the use of a computer system to assist with the tasks of editing and printing documents and the use of the telephone system to transmit data from one location to another.
electronic mail 3, 11
text handling 9, 21, 23, 43
word processing 3, 8, 19, 22
word processor 1, 3, 9-11, 22, 35
Thesaurus: a lexicon of words and phrases classified according to meaning or ideas. See also Computer
Touch screen: an input device which senses the position of a user's contact with the screen of a computer monitor. See also Hardware
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Validity: the extent to which stored data is free of errors. Reliable computer systems perform checks in order to reduce the number of errors. See also Data, Data representation
Viewdata: See Teletext
Word processing: A computer applications package which can be used for creating, amending, formatting and printing text and tables. See also Application, Text handling