Grenade cooking is when you pull the pin and hold the grenade a few second longer than normal, so as to give your opponent less time to react when it lands next to them.
There are a number of PC games that are actually based in real-life historical events. Some allow players to step into the shoes of a major historical figure while some give a chance to re-write history.
Rules are rules, sure, but what about the people who make their own? Since many people and groups have their own servers for hosting Call of Duty 4 games, you’re like to encounter a variety of differences in gameplay.