Unix

The Unix operating system got its start in 1969 at Bell Laboratories and was written in assembly language. In 1973, Ken Thompson and Dennis Ritchie succeeded in rewriting Unix in their new language C. This was quite an audacious move; at the time, system programming was done in assembly in order to extract maximum performance from the hardware. The concept of a portable operating system was barely a gleam in anyone's eye.

The creation of a portable operating system was very significant in the computing industry, but then came the problem of licensing each type of Unix. Richard Stallman, an American software freedom activist and programmer recognized a need for open source solutions and launched the GNU project in 1983, later founding the Free Software Foundation. His goal was to create a completely free and open source operating system that was Unix-compatible or Unix-like.

Linux

In 1987, the source code to a minimalistic Unix-like operating system called MINIX was released by Andrew Tanenbaum, a professor at Vrije Universiteit, for academic purposes. Linus Torvalds began developing a new operating system based on MINIX while a student at the University of Helsinki in 1991. In September of 1991, Torvalds released the first version (0.1) of the Linux kernel.

Torvalds greatly enhanced the open source community by releasing the Linux kernel under the GNU General Public License so that everyone has access to the source code and can freely make modifications to it. Many components from the GNU project, such as the GNU Core Utilities, were then integrated with the Linux kernel, thus completing the first free and open source operating system.

Linux has been adapted to a variety of computer systems of many sizes and purposes. Furthermore, different variants of Linux (called Linux distributions) have been developed over time to meet various needs. There are now hundreds of different Linux distributions available, with a wide variety of features. The most popular operating system in the world is actually Android, which is built on the Linux kernel.