A level revision

System software

System software controls aspects of the operation of the computer. There are 4 types or categories of system software.

Operating system

The operating system acts as an interface between the user and the computer's hardware. This provides a virtual machine

An operating system is a collection of programs which interact with application software to allow users to perform tasks on the computer such as saving a file to the hard disk. The operating system will interpret a command from the user into instructions the hardware can understand.

Library programs

A library program is a software application which is shared between a number of applications to perform common tasks.

Utility programs

Utility programs are designed to carry out tasks commonly required by users and to help manage the computer. Disk defragmenters and virus scanners are two good examples of utility programs.

Translators

As processors can only work in binary, called machine code, a translator is required to turn instruction, commands and statements in a programming language such as C++ into instructions the computer can understand.