AQA GCSE Computer Science key terms

System software that manages a computer's hardware and software resources and provides an interface between the user and the hardware.

The rules determining which operations are evaluated first in an expression.

A logical operation that produces 1 when at least one input is 1, including when both are 1. Written using a plus: $A+B$.

A gate that outputs 1 when at least one input is 1, including when both inputs are 1.

The enclosing structure that contains another selection structure or loop.

Data or information sent from a program to an output device, such as text displayed on a screen.

A horizontal line above a Boolean input or expression, indicating that NOT applies to everything beneath the line.

A condition in which a numerical result is too large to be represented using the available bits.

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

A variable in a subroutine definition that receives an input value. AQA also uses this term for the value supplied when the subroutine is called.

A traversal through the items being checked by an algorithm; in bubble sort, a pass compares successive adjacent pairs.

A secret sequence of characters used to authenticate a user before granting access to an account or system.

A software change released to fix a problem, such as a security vulnerability.

A controlled, authorised attempt to gain access to computer resources without the normal means of access, used to identify security vulnerabilities.

A network connecting devices close to an individual, such as a phone and headphones connected using Bluetooth.

Data that identifies, or can be used to identify, an individual, such as a name, address or identifiable location record.

A cyber attack intended to redirect a website's traffic to a fake website.

Fraudulently obtaining private information, often through an email or SMS that pretends to come from a trusted source.

A single picture element in a bitmap image, with one colour.

The value associated with a digit’s position in a number. In binary, the place values from right to left are 1, 2, 4, 8 and so on.

Readable text that has not been encrypted.

A rigid disc coated with magnetic material inside a hard disk drive.

The ability to transfer a program between different computer architectures with little or no change to its source code, provided suitable translation tools are available.

A loop that tests its condition after executing its body, so the body executes at least once.

A number obtained by multiplying 2 by itself a whole number of times, such as $2^1 = 2$, $2^2 = 4$ or $2^3 = 8$.

A loop that tests its condition before executing its body, so the body may execute zero times.

A word or symbol placed before a unit to indicate a multiple of that unit, allowing large quantities to be written more compactly.