Doom is a first person shooter published by Id Software in 1993. It is said to be the another landmark of first person shooter after Wolfenstein.
The graphics engine of Doom was again developed John Carmack. There are many improvements if compared to Wolfenstein, notably the height projection to create ground with different height, lighting system and the support of custom expansion (WADs).
The story of Doom happens in near future where humankind have setup bases in Mars. UAC is the corporation who control the operation in Mars. The UAC is a multi-planetary conglomerate with radioactive waste facilities on Mars and its two moons, Phobos and Deimos. The militaty has used the remote facilities on Phobos and Deimos to conduct varios secret projects, including reaserch on inter-dimensional travel.
Recently, the Gateways have grown dangerously unstable. Military volunteers entering them have either disappeared or been stricken with a strange form of insanity - babbleing vulgarities, bludgeoning anything that breathes, and finally suffering an untimely death of full-body explosion. Matching heads with torsos to send home to the folks became a full-time job. Latest military reports state that the research is suffering a small set-back, but everything is under control.
A few hours before the game start, Mars received a distress message from Phobos saying that "something fraggin' evil is coming out of the Gateways!". We have been sent to the moon to find out what happen there.
The original Doom has problem with music and sound effects playback. The v1.4 has solved the problem and some other bugs. You can download Doom v1.4 here.