Call of Duty is a 2003
first-person shooter video game developed by
Infinity Ward and published by
Activision, the first installment of the
Call of Duty video game series. The game simulates the
infantry and
combined arms warfare of
World War II. The game is based on the
Quake III: Team Arena engine. It was accompanied in September 2004 by an expansion pack,
Call of Duty: United Offensive, which was produced by Activision, and developed by
Gray Matter Interactive, with contributions from
Pi Studios.
Call of Duty is similar in theme and gameplay to
Medal of Honor, as it is made out of
single-player campaigns and missions. However, unlike
Medal of Honor, the war is seen not just from the viewpoint of an American soldier but also from the viewpoint of British, Canadian, and Soviet soldiers.