Brazilian Jiu-Jitsu
Brazilian Jiu-Jitsu (BJJ) is a ground-based martial art focused on using leverage and positions to apply submission holds against the opponent or subdue him with superior positioning. BJJ was made famous by Royce Gracie as he showcased the superiority of the art against larger opponents in the early UFC's.
BJJ is still used by all mixed martial artists. It has been adopted by law-enforcement and military personnel as well. It has become one of the most widely-studied martial arts in the United States and is an excellent self-defense mechanism. The techniques used in BJJ allow all ages and body shapes to excel in martial arts.