Linux is a high performance, yet completely free, Unix-like operating system that are suitable for use on a wide range of computers and other products. Most distributions(i.e., versions) consist of a kernel (i.e., the core of the operating system) together with hundreds of free utilities and application programs in a coordinated package.
A narrower, and somewhat less common, meaning of the termLinux is just the kernel itself. However, when referring to just the kernel, usually the expression the Linux kernel is used.
Linux was started as hobbies in 1991 by Linus Torvalds while a student at the University of Helsinki (in Finland) because he was unhappy with the MS-DOS operating system that came with his new personal computer. He greatly preferred the much more powerful and stable UNIX that he had been using on the university's computers, but he was not able to afford the high licensing fees for any of the commercial versions then available. Today, Torvalds remains the spiritual leader of the Linux movement, and he still coordinates the development of the Linux kernel.

Rapid Growth

The use of Linux by individuals, corporations, government agencies and academic institutions around the world has been growing swiftly1, and many computer experts think that it will eventually become the most widely used operating system for many or most types of applications.
This rapid growth is a result of several factors including (1) the major advantages that Linux has over other operating systems (including over the other Unix-like operating systems and the Microsoft Windows family of operating systems), (2) the rapid progress that is being made on further improving the performance and increasing the functions of Linux, (3) the expanding array of high-quality application programs, (4) the growing awareness by individuals, businesses and other organizations throughout the world of the advantages of Linux and (5) an increase in the number of people who are familiar with installing, administering and using Linux.