Updated: 06/07/2019 by Computer Hope

Coined by Brian Kernighan, Unix or UNIX (not an acronym) is an operating system developed by members of the MULTICS team at the Bell Laboratories starting in the late 1960s, many who also help create the C programming language. Today, Unix is not just the work of a couple of programmers; organizations, institutes, and other individuals have contributed significant additions to Unix and its variants, making it a widely used and popular operating system.

Unix is primarily a command line based operating system with additional applications, such as X Window, to give a graphic oriented operating system similar to Windows. Since Unix is often used from the command line, there are various shells. A shell is a large add-on or modification of the Unix operating system, to determine the shell you can type echo $SHELL at the Unix prompt. When typing this command, a response like "/bin/csh" is displayed, which indicates you are logged into a C shell. Bourne shell is "/bin/sh" and Korn shell is "/bin/ksh."

Is it Unix or UNIX in all caps?

When first introduced, UNIX was a trademark of Bell Laboratories (AT&T), which is now owned by The Open Group, who obtained the trademark in 1993. Today, Unix and UNIX are accepted as correct and interchangeable when referring to the operating system. However, if you are referring to the trademark, it would be more appropriate to use UNIX instead of Unix.

Unix distributions, flavors, and variants

There are dozens of Unix distributions that have been released since its initial release. Below are a few of the distributions we have currently listed on our site.

Linux, Operating system terms, POSIX, YAUN