Brazilian Jiu-Jitsu "BJJ" is a martial art and combat sport that focuses on grappling and  ground fighting with the goal of gaining and maintaining dominant position and using joint-locks and chokeholds to force an opponent to submit by tapping out.. It promotes the principle that a smaller, weaker person using leverage and proper technique can successfully defend against a bigger, stronger fighter. Brazilian Jiu-Jitsu  permits a wide variety of techniques to take the fight to the ground after taking a grip. Once the opponent is on the ground, a number of maneuvers (and counter-maneuvers) are available to manipulate the opponent into a suitable position for the application of a submission technique. Achieving a dominant position on the ground is one of the trademarks of the Brazilian Jiu-Jitsu style, and includes effective use of the guard position to defend oneself from bottom, and passing the guard to dominate from top position with side control, mount, and back mount positions