Call of Duty is a 2003 first-person shooter video game developed by Infinity Ward and published by Activision. It is the first of many installments in the Call of Duty franchise. The game simulates infantry and combined arms warfare of World War II using a modified version of the id Tech 3 engine built for Quake III: Team Arena. Much of its theme and gameplay is similar to the Medal of Honor series, however Call of Duty showcases multiple viewpoints staged in the British, American, and Soviet theaters of World War II.