Microsoft Windows NT

Microsoft Windows NT (Windows "New Technology") is an operating system produced by Microsoft Corporation. It was originally based on OS/2 3.0, a joint project between Microsoft and IBM. The collaboration fell apart, and IBM continued to market the previous version OS/2 3.0 (later rebranded OS/2 Warp) while Microsoft renamed their version to MS Windows NT, changing the main API to a 32-bit version of its MS Win16 API.

Microsoft hired a group of developers from Digital Equipment Corporation to build a new system. Many elements of NT reflect the earlier DEC experience with VMS and RSX-11

NT enjoyed more success than OS/2, due to its feature promises that were never fully realized and to Microsoft's market prowess.

The following are the major releases of Windows NT :

• Microsoft Windows NT 3.1
• Microsoft Windows NT 3.5
• Microsoft Windows NT 3.51
• Microsoft Windows NT 4.0

Microsoft Windows 2000 and Windows XP are later versions of Windows NT:

• Microsoft Windows 2000 (Version 5.0)
• Microsoft Windows XP (Version 5.1)

Windows NT is now simply called Windows:

• Microsoft Windows Server 2003 (Version 5.2)

Version 3.1, the first version based on "NT Technology" (which may have been numbered perhaps to match that of Windows 3.1, or perhaps to best OS/2 Warp 3), came in "Advanced Server" and "Workstation" editions. From Version 3.5, "Advanced Server" was renamed "Server". From Version 5.0 (Windows 2000) onwards, "Workstation" was renamed "Professional". A "Home Edition" was introduced with Version 5.1 (XP), to mark the discontinuation of the previous MS-DOS based Windows system.

The acronym WNT was acknowledged by its ex-Digital developer, Dave Cutler, to be a pun on VMS -- obtained by shifting each letter one position in alphabetical order, akin to the urban legend regarding the name of IBM and the villanous computer HAL 9000, as featured in the film 2001: A Space Odyssey.

NT uses a highly layered design, with the hardware hidden from the NT kernel by a hardware abstraction layer, and most operating system API functionality provided by API-specific interface modules that present specific functionality such as the Win32, OS/2, DOS and POSIX system call compatibility environments.

See History of Microsoft Windows, Blue screen of death.

External links

• Windows NT and VMS: The Rest of the Story, discussion of ancestry of NT by Mark Russinovich
• A Brief History of the Windows NT Operating System a Microsoft Presspass Fact Sheet