Many people credit Ken Thompson of AT&T with inventing the Unix operating system and, in a sense, they're right. Thompson wrote the first Unix version in 1969 at AT&T's Research Division of Bell ...

In 1996, Microsoft introduced OpenNT, its first Unix subsystem for Windows NT. In 1998, it was rebranded as Interix and remained as a separate product until it became part of Microsoft Windows ...

Unix was developed as a command line interface in the early 1970s with a very rich command vocabulary. DOS followed more than a decade later for the IBM PC, and DOS commands migrated to Windows.