A hammer is a type of throw. Instead of the top (printed side) of the disc being thrown facing up, the underside of the disc faces the sky (during the throwing motion and during the flight of the throw). The throw resembles an (overhand) baseball pitcher's motion, although with the release point often being over the crest of the head instead of the top of the shoulder. The release is similar to a forehand release (just angled differently). The hammer is usually thrown to a receiver on the weak side of the field (break the mark). It often flies higher, and descends more rapidly than a regular (forehand, backhand) throw. Because the disc flies upside down/sideways, the rim of the disc is not catching any air, and when the flight of the hammer is not parallel to the ground, the disc can travel very quickly. The picture above shows a hammer in mid-air. The thrower has released the hammer above his shoulder, and the disc is traveling away from him at a 45 degree angle. The other team looks like they are playing a zone, and the throw is probably to a somewhat stationary player off the picture to the right. The hammer has the advantage of going over the mark (the right partially obscured person) to what is probabably an unguarded player (or a player who is unguarded on the mark side).