BJJ revolves around the concept that a smaller, weaker person can successfully defend themselves against a bigger, stronger, heavier opponent by using leverage and weight distribution, taking the fight to the ground and using a number of holds and submissions to defeat them. BJJ training can be used for sport grappling and self-defense situations. Sparring, commonly referred to as "rolling" within the BJJ community, and live drilling plays a major role in training and the practitioner's development. BJJ can also be used as a method of promoting physical fitness, building character, and as a way of life.