The IW Engine is a game engine developed by Infinity Ward, based on id Tech 3, which was first used on the highly successful game Call of Duty 2. Since then, it has been continually upgraded and used on the games Call of Duty 4, Call of Duty: World at War, Call of Duty: Modern Warfare 2, and Call of Duty: Black Ops.

Aura636 says

6/10 - Agree Disagree

This is a nice engine, but it has been miss used. They only slightly update this engine for each game, if at all.