AQA GCSE Computer Science key terms

Hardware, software or files that can be made available for computers to use, such as a shared printer.

The data returned by a database query.

A value passed back from a function to the code that called it.

The ability of a program to cope with incorrect or unexpected input without failing.

Read Only Memory: non-volatile main memory that holds the instructions needed to start a computer. During normal operation, its contents are read rather than changed.

The starting node of a tree, from which every character's path begins.

A consecutive sequence of identical data values, such as neighbouring pixels of the same colour in a bitmap row.

A lossless compression method that represents consecutive identical data values using a run length and the repeated value.

A lossless compression method that represents each sequence of consecutive identical values using its length and the repeated value.

A measurement of a sound wave’s amplitude at a particular moment, stored digitally as a binary value.

The number of bits used to store each sound sample.

Taking measurements of an analogue signal's amplitude at regular time intervals to help create a digital representation.

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

The part of a program in which a variable can be accessed.

The part of a sorted collection that could still contain the target, bounded by its lowest and highest remaining indices.

Non-volatile storage that is not directly accessible by the CPU, used to retain programs and data.

A software update that fixes a known security weakness.

A programming structure that chooses which instructions to execute according to a condition.

Executing statements in order, one after another.

A pattern in which each successive character within a group has a code one greater than the previous character.

Hardware or software that provides services or resources to other computers on a network, such as access to shared files.

An SQL clause that specifies which columns to change and the new values to store.

Obtaining private information by observing it over someone's shoulder, such as watching them enter a cashpoint PIN. Also called shoulder surfing.

A component whose failure can make a whole system, or a service used by many users, unavailable.

A prefix from the International System of Units that represents a power of 10, such as kilo for $10^3$.

Simple Mail Transfer Protocol: a protocol used to send email from a client to a mail server and transfer email between mail servers.

Targeting people who use or have access to computer systems to obtain confidential information or persuade them to carry out actions that compromise security.