High Quality Content by WIKIPEDIA articles! Windows NT 4.0 is a preemptive,graphical and business-oriented operating system designed to work with either uniprocessor or symmetric multi-processor computers. It was part of Microsoft`s Windows NT line of operating systems and was released to manufacturing on 31 July 1996. It is a 32-bit Windows system available in both workstation and server editions with a graphical environment similar to that of Windows 95.