DOOM

Doom95 is an official port of Doom to the Microsoft Windows operating system, and is included in many later releases of The Ultimate Doom, Doom II, and Final Doom. This port was developed by a team at Microsoft headed by Alex St. John, the creator of the DirectX specification. It was to serve as a flagship for the new technology, and was initially released as a preview on the Games for Windows 95 CD released in November 1995 by Microsoft, with a full release following on August 20, 1996.

Work on a port of Doom to Windows began at Microsoft in mid-1994, then targeting Windows 3.11 and up via the new Win32s and WinG technologies, under the name of WinDoom. This initial work was done by a team started by Gabe Newell, who later co-founded Valve Software and developed Half-Life. While two public betas were released, this version of the code base was eventually shelved.

In late 1995, Doom was estimated to be installed on more computers worldwide than Microsoft's new operating system Windows 95, despite million-dollar advertising campaigns for the latter. The game's popularity prompted Bill Gates to briefly consider buying id Software, and led Microsoft to repurpose their Doom porting project into a promotion of the new operating system as a gaming platform. One related presentation, created to promote Windows 95 as part of Microsoft's Judgment Day event, had Bill Gates digitally superimposed into the game, killing zombies with a shotgun (rather strangely while holding it by the barrel with both hands) between segments of exposition. Microsoft stated that this release heralded the end of the reign of MS-DOS (though ironically enough, the Windows 9x series of operating systems are a hybrid 16/32-bit architecture that still depended on DOS at least in a vestigial way).

Version 2.0.0.1 of Doom 95, containing the shareware version of Doom and an earlier version of the configuration tool, was released as part of the Games for Windows 95 CD released by Microsoft in November 1995. The compile date for this version is November 15, 1995. This version contained a bug in the demo playback system that causes the player to become a resurrected ghost. A full release, dubbed version 3.0, followed on August 20, 1996.