Windows NT 3.1

Windows NT 3.1 is the first release of Microsoft's Windows NT line of server and business desktop operating systems, and was released to manufacturing on July 27 1993. The version number was chosen to match the one of Windows 3.1, the then-latest GUI from Microsoft, on account of the similar visual appearance of the user interface. Two editions of NT 3.1 were made available, Windows NT 3.1 and Windows NT Advanced Server.
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<operating system> Microsoft's first version of Windows NT, released in September 1993, price UKP 395, after having been in beta-test for as long as anyone could remember.
The person responsible for VMS on the DEC VAX [who?] was also responsible for Windows NT. Incrementing each letter in VMS yields WNT.
http://www.win2000mag.com/Articles/Index.cfm?ArticleID=4494.
(2000-08-12)