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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.

The operating system has four main parts:

• The KERNEL
• The DEVICE DRIVERS
• The USER INTERFACE
• The SYSTEM UTILITIES

The next few pages describe the different types of operating systems. But they all share these common features.