Unix

UNIX is a kernel-type developed by AT&T and Bell Labs in the early 1970's. Originally a non-free system, many forks were made leading to the *nix (or UNIX-Like) systems we see today, such as the GNU/Linux System, The Hurd Micro-kernel, The Berkly Software Distribution (and it's many derivatives), etc.

UNIX was originally created by the same people who invented the C Programming language. Their goal was to make a cheap, easy-to-use system written in their new language. This is where the UNIX Philosophy comes from.

The UNIX Philosophy

(Not to be confused with The GNU Philosophy

In the age of UNIX, Computers were very slow and expensive to run. This is where The UNIX Philosophy came from. The UNIX Philosophy simply states that a single program should be dedicated to one single thing, and do it well. This allowed many small programs to be a part of the UNIX system, all working together to perform basic system tasks.

What does God think?

RMS never liked UNIX. He only chose UNIX for The GNU Project because he thought it was a good-enough model, and better than anything else at the time. However, he commonly uses UNIX and other *nix systems since the early 1980's.