Edexcel GCSE Computer Science key terms

Random access memory: the main memory holding instructions and data currently being used by the CPU.

The maximum distance over which a connection's signal can reach and provide communication.

A validation check that a numerical value falls within specified limits.

Malware that blocks access to a computer or its data, often by encrypting files, and demands payment to restore access.

A natural material used to manufacture a product, such as a metal, oil or sand.

How easily a person can read and understand a program’s code.

A numeric data type that can represent values with a fractional part. Python uses float.

A collection of related fields describing one item, such as one student's number, name and score.

Planned steps for restoring data, software and working systems after a failure, attack or disaster.

Processing waste to recover materials that can be used to make new products.

Changing a program to better meet its requirements, for example by correcting behaviour, completing functionality or improving readability.

A very small, fast storage location inside the CPU that temporarily holds information needed during processing.

An operator that compares two values and produces a Boolean result: True or False.

Repeatedly executing an instruction or block of instructions using a loop.

The time between acquiring a digital device and replacing it with another.

The number of pixels used to represent an image, commonly expressed as its width × height in pixels. Pixel density describes how closely pixels are packed when displayed or printed.

Hardware, software or data that devices can access or use, such as a printer, application or shared file.

The result sent back by a function to the code that called it.

The design and use of computer-controlled machines that carry out physical tasks.

Software designed to handle unexpected errors or conditions without crashing or failing unnecessarily.

A networking device that forwards data packets between different networks towards their destination.

An error that occurs during execution, such as division by zero. If it is not handled, it stops the program.

The avoidance or reduction of harm to people caused by a system's operation or decisions.

A measurement of a sound signal’s amplitude at one point in time.

The time between successive sound samples.

The number of sound samples taken each second, measured in hertz (Hz).

A set of rules used by the operating system to prioritise processes and decide which gets processor time.