Brazilian Jiu Jitsu (BJJ) is a martial art, combat sport, and a self defense system that focuses on grappling. BJJ promotes the concept that a smaller, weaker person can successfully defend against a bigger, stronger opponent by using proper technique, and leverage. This is done by taking the fight to the ground and applying submissive holds involving joint-locks and chokeholds to defeat the opponent.
Training methods include: technique drilling, positional drilling, and full sparring, otherwise known as rolling. Rolling, also know as grappling, is when each person tries to submit their opponent using any legal technique. Physical conditioning is also an important part of training.
While training, Brazilian Jiu-Jitsu focuses on submissions and holds, without the use of strikes. This allows practitioners to practice at full speed, and with full power, resembling the effort used in a real life situation.