All modern computers have some form of operating system which users generally take for granted. The operating system makes it possible to communicate with the software and hardware that make up a typical computer system.
This textbook has been written to provide the knowledge, understanding and practical
skills that a student would need for the Cambridge International Examinations
Computer Science IGCSE and GCE O Level courses.
As you progress through this book you will begin to realise how complex computer systems really are. By the time you reach Chapter 12 you should have a better understanding of the fundamentals behind computers themselves and the software that controls them
The HEXADECIMAL SYSTEM is very closely related to the binary system. Hexadecimal (sometimes referred to as simply "hex") is a base 16 system and therefore needs to use 16 different "values" to represent each digit.