Call of Duty 4: Modern Warfare sports a huge array of improvements over its predecessors. Upgraded graphics, a dizzying array of textures, dozens of weapons and a host of seemingly minor gameplay tweeks.
Like Call of Duty 3, you have the ability to throw grenades back at your enemies. While it may seem insignificant, this will save your skin more times than you can imagine. Your character also has the benefit of a GPS, giving you a small minimap on the menu screen. You also have the ability to sprint, hold your breath when firing sniper rifles (a holdover from Call of Duty 2, but a realistic touch) and like the original Call of Duty, several weapons now have multiple firing modes (most notably weapons with attached grenade launchers.)

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Call of Duty 4 makes some time for “bonus” content. You get to spend a mission in an AC-130 gunship, covering your former self and allies as they rush to extract a VIP from hostile territory in Russia. You also get to take time out from a few missions to use Javelin Missile Launchers to destroy enemy tanks. Moments like these are seamlessly integrated into the game. You take a few moments to do something different, but you don’t hardly notice that you’re doing it. Without giving too much away, the game takes a moment out from the action to show a great tragedy from a point of view that is up close and very personal.
Call of Duty 4 also sports improved AI, for both your allies and enemies. Far from being the only soldier with a unit following in the distance, Call of Duty 4 has you working with a team almost every step of the way. Chances are high that if you try to leave your men behind, you will get killed.
One of the coolest features of Call of Duty 4 that separates it from every other FPS out there is the introduction of “soft cover.” This means that thin objects like sheet metal and wood will no longer stop bullets. They will decrease the damage they do, but bullets will now pass through thin materials and into you if you are not careful!