Components of a computer system

Hardware.

The physical parts of the computer e.g. the keyboard.

Software.

A group of instructions that the hardware needs to tell it what to do.

Applications software.

The set of programs that allow the user to do something useful with the computer.

Operating system.

This is the programs that allow the hardware to work.

Programs.

A groups of instruction that the hardware needs to tell it what to do which are collected together in groups of instruction.