Brazilian Jiu-Jitsu (BJJ) is a martial art a self defense system that focuses on grappling and especially ground fighting. BJJ emphasizes getting an opponent to the ground in order to use ground fighting techniques and submission holds involving joint-locks and chokeholds. Fundamental to Jiu-Jitsu is that on the ground, physical strength can be offset or enhanced by an experienced grappler who knows how to maximize force using mechanical advantage instead of pure physical strength