Edexcel GCSE Computer Science key terms

A sorting algorithm that repeatedly splits a list into smaller lists, then merges them back together in order.

A network arrangement with connections between multiple devices, providing alternative routes for data.

Additional data describing other data. For a bitmap image, this can include its dimensions and colour depth.

An integrated circuit containing a processor, memory and input/output facilities, used to control a device.

A short, memorable text command representing an assembly-language instruction, such as LDA for a load instruction.

A simplified representation of a real-world object, environment, action or concept, retaining the features needed for a particular purpose.

An operation that returns the remainder after division, written % in Python.

The leftmost bit in a binary pattern. In an 8-bit unsigned number its place value is 128; in an 8-bit two’s complement number its place value is −128.

Authentication that requires evidence from more than one type of factor, such as a password and possession of a registered phone.

Changing a number’s sign while keeping its magnitude unchanged; for example, changing +5 to −5.

Two or more devices connected so that they can exchange data and share resources.

Activities designed to protect a network and its data from internal and external threats.

The arrangement of devices and the connections between them in a network.

A weakness in a network that an attacker could exploit to gain unauthorised access to information or resources.

A group of 4 bits.

Storage that retains its contents without an electrical power supply.

Typical valid input that a program is expected to accept and process.

A logical operator that reverses a Boolean value: True becomes False, and False becomes True.

The number of different digit values available in a number system: for example, binary has base 2.

A data structure in which one index is needed to access an individual item.

Software whose source code is available under a licence permitting users to inspect, modify and redistribute it under stated conditions.

A value on which an operator acts. In 8 + 3, the operands are 8 and 3.

System software that controls a computer's hardware and software and provides an interface for users.

A symbol or keyword that performs an operation on one or more values.

Storage that uses a laser to read patterns on the surface of a disc.

A logical operator that produces True when at least one Boolean condition is true, including when both are true.

Information produced by a program, such as a message displayed on screen.