What is the difference between BB guns and airsoft guns?

Airsoft guns often replicate real guns (such as M16, AK-47, ect,) and shoot little plastic pellets. Airsoft guns are commonly used for the sport of airsoft, which involves a simulation of war where you try to get the other players "out" by shooting them.

BB guns are not meant to shoot people. They are single-action where airsoft guns are commonly automatic. They shoot small metal BBs which are generally meant for target practice. They generally have a higher velocity than airsoft guns and are dangerous to shoot at people but are not capable of killing anyone.