The Linux environment is based on the UNIX operating system. Versions of the UNIX operating system run on many different computer systems--microcomputers, PCs and mainframes.

The operating system is a set of programs that manages all computer operations and provides a link between the user and system resources.

There are three main parts of the operating system:

• Kernel - manages the hardware
• Shell - user interface with the kernel
• File system - used to store and retrieve data