OCR GCSE Computer Science key terms

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 program code.

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.

The base-10 number system, using digits 0–9. Its place values are ones, tens, hundreds and so on.

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.