Unix
Family of computer operating systems
Unix (YOO-niks; trademarked as UNIX) is a family of multitasking, multi-user computer operating systems that derive from the original AT&T Unix, the development of which started in 1969 at the Bell Labs research center by Ken Thompson, Dennis Ritchie, and others. Initially intended for use inside the Bell System, AT&T licensed Unix to outside parties in the late 1970s, leading to a variety of both academic and commercial Unix variants from vendors including Berkeley Software Distribution (BSD), Microsoft (Xenix), Sun Microsystems (SunOS/Solaris), HP (HP-UX), and IBM (AIX). The early versions of Unix, which are retrospectively referred to as "Research Unix", ran on computers such as the PDP-11 and VAX; Unix was commonly used on minicomputers and mainframes from the 1970s onwards.
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