Computer Science key terms

A unit of data sent across a network, containing part of the transmitted data and information needed to deliver it.

UK legislation that works alongside the UK GDPR to regulate the handling of personal data and protect individuals’ rights.

A way of organising data so that a program can store, access and process it.

Unauthorised taking or copying of data, such as personal information or account credentials.

The rate at which data is actually transferred successfully over a network connection.

A classification describing the kind of value represented and the operations that can be performed on it.

A tool that lets a programmer control execution and inspect variable values to investigate errors.

The process of finding and correcting errors in a program.

Breaking a complex problem down into smaller, more manageable problems.

The process of decoding compressed data into a usable form. With lossless compression, this restores the exact original data.

The process of converting ciphertext back into plaintext using the appropriate algorithm and key.

A value used to convert encrypted data back into its readable form.

Designing a program to anticipate misuse and handle unexpected or invalid inputs safely.

Software that reorganises fragmented files on a magnetic hard disk drive so that their parts are stored together, improving access speed.

A base-10 number system using the digits 0–9, with place values such as 1, 10 and 100.

An attack that overwhelms a server or network with traffic or requests, preventing legitimate users from accessing its services.

Software that enables an operating system to communicate with and control a particular hardware device.

A data structure that stores key–value pairs. A Python dictionary can represent a record, with keys acting as field names.

Inequality between people in their access to digital technology and their ability, skills or confidence to use it.

An approach that breaks a problem into smaller problems, solves them and combines their results.

A Domain Name Service, made up of multiple Domain Name Servers, that looks up domain names and returns their corresponding IP addresses.

A human-readable name, such as example.org, used to identify a website rather than remembering its server's numeric IP address.

Following an algorithm manually with chosen input values, recording changes to variables and outputs.

How well a storage device or medium withstands physical damage, such as knocks, drops or scratches.

The length of audio contained in a sound file, measured in seconds.

A tool used to enter, change and save a program’s source code.

Discarded electrical or electronic equipment, such as unwanted computers and smartphones.

An individual value stored at a position in an array.

A computer system built into a larger device or system to perform a dedicated function or limited range of tasks.

The conversion of readable data into unreadable data using an algorithm and a key.