Microsoft and UNIX

It may come as a shock for some of the younger people, but in the past Microsoft had a UNIX: Xenix. Xenix was Microsoft's version of Unix intended for use on microcomputers. On the late 70's, Microsoft purchased a license for Version 7 Unix from AT&T, running on the historical minicomputer PDP-11 (I learned assembly language on PDP-11, yes, I'm that old), and was ported to the 8086 in 1982.

In 1987 Microsoft transferred ownership of Xenix to SCO, renaming it to SCO UNIX, but continued to use Xenix internally as late as 1992. As a result of Microsoft's walk on the UNIX world:

In the late 1980s, Xenix was, according to The Design and Implementation of the 4.3 BSD UNIX Operating System, "probably the most widespread version of the UNIX operating system, according to the number of machines on which it runs".

Unfortunately SCO is closing, so Microsoft's UNIX is about to end. Luckily for us, Microsoft as a successful heir on their dissemination strategy: Linux :)