Counter-Strike: Source

Overview
Counter-Strike: Source (officially abbreviated CS:S ) is an FPS video game developed by Valve Corporation. It is a complete remake of Counter-Strike using the Source game engine. As in the original, Counter-Strike: Source pits a team of counter-terrorists against a team of terrorists in a series of rounds. Each round is won either by completing an objective (such as detonating a bomb or rescuing hostages) or by eliminating all members of the enemy team.