Doom 3[b] is a 2004 survival horror first-person shooter video game developed by id Software and published by Activision. Doom 3 was originally released for Microsoft Windows on August 3, 2004, adapted for Linux later that year, and ported by Aspyr Media for Mac OS X in 2005. Developer Vicarious Visions ported the game to the Xbox, releasing it on April 3, 2005.
Doom 3 is set on Mars in 2145, where a military-industrial conglomerate has set up a scientific research facility into fields such as teleportation, biological research, and advanced weapons design. The teleportation experiments open a gateway to Hell, resulting in a catastrophic invasion of the Mars base by demons. The player controls a space marine who fights through the base to stop the demons attacking Mars and reaching Earth.
Doom 3 is the first reboot of the Doom series, ignoring the events of the previous games. Doom 3 utilizes the id Tech 4 game engine, which has since been licensed out to other developers, and later released under the GNU General Public License v3.0 or later in November 2011.