Edexcel GCSE Computer Science key terms

A rule that determines what a user is allowed to access or do, such as viewing or editing a shared file.

The responsibility to explain decisions and outcomes, answer for them and address problems when they occur.

An output device that produces a physical action under computer control, such as a motor opening a vent.

A set of connections carrying memory addresses from the CPU to identify locations to read from or write to.

A finite sequence of precisely defined steps for solving a problem.

How economically an algorithm uses processing time and memory to complete its task.

A tendency in a computer system's decisions that produces unfair outcomes, such as favouring one group over another.

The size of a sound wave’s variation from its resting level. Greater amplitude means a louder sound.

A signal that varies continuously over time and can take values throughout a continuous range.

A device that converts a continuously varying analogue signal into digital values that a computer can store and process.

A logical operator that produces True only when both Boolean conditions are true.

Software that detects malicious software, helps prevent infection and can remove malware already present on a system.

A file-opening mode that preserves existing contents and adds new data at the end of the file.

An actual value supplied to a subprogram when it is called.

The CPU component that performs arithmetic operations, such as addition, and logical operations, such as comparisons.

A symbol that instructs a program to perform a mathematical calculation on numerical values.

A shift used with signed binary integers. A right arithmetic shift copies the original sign bit into vacated left-hand positions; a left arithmetic shift moves bits left and inserts zeros on the right.

An ordered, fixed-length sequence of items of the same data type. In the Edexcel PLS, arrays are represented using Python lists.

The ability of a computer or computer-controlled robot to perform tasks commonly associated with intelligent beings, such as recognising patterns and making decisions.

American Standard Code for Information Interchange: a character set that uses 7-bit codes, giving 128 possible codes.

A low-level programming language that represents processor instructions using short text commands called mnemonics. It must be translated into machine code before execution.

Storing a value in a variable; Python uses = for assignment.

An instruction that stores a value in a variable or another storage location.

A digital record of changes that identifies who made each change, what they changed and when.

The process of verifying a user's claimed identity before allowing access to a system or account.

A separate copy of data kept so that the data can be restored if the original is lost, damaged or unavailable.

Exploiting curiosity or greed by offering something appealing, such as a free download, to lure someone into compromising security.