Graphic content\n\n Call of Duty: Modern Warfare 2 and Warzone are specifically targeted at mature audiences. Both games depict gunshot wounds, dismemberment, and exposed viscera. The in-game dialogue regularly includes profanity. Some levels include elements such as mutilated corpses and drug paraphernalia.
The Call of Duty series games are made in IW engine by Infinity Ward. You probably would've seen the name when you start any COD series game. Almost every game shows the game engine which it is built in. The IW game engine uses c++.