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.
The IW Engine has been used almost exclusively to make Call of Duty games. Here is a look at some over the years.
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GAH THIS IS UNREAL ENGINE 3!!
Actually, it's idTech 3.
LOLz I hate it when companies fo that