2. What is an operating system?

An operating system is the core software that allows a computer to run as an useful device. It manages the hardware, the user interface and all other software running on the computer.

Without an operating system, a computer is just a collection of components heating up the room as no-one would be able to make any practical use of the machine.

A large number of operating systems have been developed over the years; each designed with a certain kind of computer in mind. For instance:

• Windows or Linux - for personal computers
• MacOS - for Macs
• Unix - for mainframes
• Symbian, Android - for mobile phones

Although these operating systems have been developed to work with very different types of computers, they all share a number of common functions:

• Providing a user interface
• Managing the computer's memory
• Managing the hardware