Xenix variant information
In the late 1970's Microsoft licensed Unix source code from AT&T, which at the time was not licensing the name Unix. Therefore Microsoft created the name Xenix. Microsoft did not sell Xenix to end-users but instead licensed the software to software OEMs such as Intel, Tandy, Altos and SCO who then provided a finished version of their own Xenix to the end-users or other customers.
SCO introduced its first version of Xenix named SCO Xenix System V for the Intel 8086 and 8088 in 1983. Today, SCO Xenix is one of the more commonly used and found versions of Xenix.