A crossbow is a weapon that has been used for centuries for warfare and hunting. It is similar in function to a compound bow or longbow, but is used much differently. In fact, you could say that the crossbow is a kind of cross between a rifle and a bow and arrow. A crossbow has a stock much like a rifle, but uses an arrow as the projectile. The user will pull back the string and lock it into place, notch a bolt, which is the equivalent of an arrow to a bow, and then use a trigger to fire the arrow.