Excel Igcse Computer Studies Glossary Essay

Actuator – It is a device that can be operated by signals from a computer or control system causing physical movement. (E.g. devices for opening windows in a computer controlled ventilation system) Algorithm – It is a sequence of instructions designed to perform a particular task and it is independent of any programming language. It includes precise details about the operations to be performed and in what order. (E.g. pseudo-code or program flow chart) Batch processing – It is a processing that doesn’t start until all the data are collected without any needs of human interaction. It uses computer during overnight. (E.g. payroll system, billing, cheque processing) CAD (Computer Aided Design) – It is the use of computer system that allows engineers and architects to design new projects by producing drawings. (E.g. designing new cars) Command-line interface – It is a set of commands instructed by the user in order to communicate with the computer and get the requirements sorted out. Compiler – It is a program that converts high-level language into machine language and converts whole program before execution. Cookies – It is a text which the user receives when in access to the internet website and gets automatically downloaded onto the user’s computer and further develops to infect a computer. (E.g. it can be blocked when the user rejects it by setting its restriction on the web page) Data integrity – It refers to the accuracy of data. Data-logging – It is an automatic capturing and storing of data readings from sensors over a period of time. (E.g. weather forecasting) De-skilling – It is replacing a semi-skilled labour with a micro-processing control system. Dry run – It is working through a program or a section of a program manually. This is useful for locating errors, particularly run time errors. E-commerce – It is an electronic commerce that allows buying and selling goods and services through the internet/computer networks. Either B2B or B2C, they still serve their products. (E.g. on-line shopping, Internet/online banking) H.J.Hong Encryption – It is a way of preventing data files that contain sensitive  information from being used if they’re stolen. Expert system – It is an application of artificial intelligence (AI) to a particular area of activity where traditional human expert knowledge and experience are made available through a computer package. (E.g. medical diagnosis) Generic software – It is a type of software that can perform many different related tasks. Intranet – It is a communication system, providing similar services to the internet solely within a particular company or organization. It makes it possible to share documents, databases and applications, using the same protocol as the internet. (E.g. more secure data) Logic gates – They are the components used in making logic circuits. Each gate has 1 or more inputs and produces a single output that depends upon the input(s). Simulation – It is a study of the behaviour of a system by using a model. (E.g. flight simulator) Structure diagram – It is a means of representing the design of a program or system and it demonstrates what happens at a program level Top-down design – It is the technic of breaking down a problem into subtasks that are sufficiently simple enough to be written as a self-contained module or procedure. (E.g. allows several programmers to work on the same large task, each module can be tested/debugged separately) Validation – It is a check on the data input and detects any data that is unreasonable and unacceptable. Video-conferencing – It is a form of an electronic communication through Internet for people who are geographically separated to transmit audio and video data. (E.g. meetings held at different locations) Virtual reality – It is a computer simulation that uses special interactive devices such as data gloves to create an artificial environment. (E.g. viewing newly constructed houses/pilot training) Virus – It is a program which replicates itself and damages files or data. (E.g. it alters the data on the infected computer without the user knowing it)