Unix is not an acronym; In 1969 Ken Thompson wrote the first version of Unix, called UNICS. The name “Unix” was intended as a pun on Multics (and was written “Unics” at first — UNiplexed Information and Computing System).
Unix is a powerful, multi-user environment. Unix was developed at Bell Labs in 1969. Examples of Unix implementations include Mac OS X/Darwin (Apple), GNU/Linux, AIX (IBM), Solaris (Sun), IRIX (SGI), and FreeBSD.
Free Unix-like operating systems
The GNU Project was launched in 1984 to develop a complete Unix-like operating system which is free software: the GNU system.
Popular Free Unix-like operating systems distributions based on GNU/Linux include
- Red Hat Enterprise Linux
- SUSE Linux Enterprise
- Debian GNU/Linux
- Mandriva Linux
- Slackware Linux
BSD-based Operating Systems
Berkeley Software Distribution (BSD, sometimes called Berkeley Unix) is A UNIX-like operating system. Check out the list of Free BSD-based Operating Systems.