Knife

The knife is the basic and only close-up melee weapon in Call of Duty 4. It isn't commonly used it singleplayer, except for missions that include stealth or reconnaissance. This weapon can be triggered by pressing V, as taught in the F.N.G mission.

Multiplayer
This weapon can be used to trigger a "Humiliation" in multiplayer maps. It is well used when a player is nearby an enemy and they are firing. The common way used to kill with the knife in close combat, is to dodge all incoming shots, get behind the enemy quickly and knife them. Another use of the knife in multiplayer can be to take out a sniper standing in a two-story building.