High Quality Content by WIKIPEDIA articles! Halo: Combat Evolved, frequently referred to as Halo: CE, or Halo 1, is a first-person shooter video game developed by Bungie and published by Microsoft Game Studios. The first game of the Halo franchise, it was released on November 15, 2001 as a launch title for the Xbox gaming system, and is considered the platform`s "killer app". With more than five million copies sold worldwide as of November 9, 2005, Microsoft released versions of the game for Microsoft Windows (ported by Gearbox Software) and Mac OS X in 2003, and the surrounding storyline was adapted and elaborated into a series of novels and comic books. The game was later released as an Xbox Original for download onto an Xbox 360 HDD.