Its most prominent feature is its competitive element, where the objective is to either throw or takedown an opponent to the ground, immobilize or otherwise subdue an opponent with a pin, or force an opponent to submit with a joint lock or a choke. Strikes and thrusts by hands and feet as well as weapons defenses are a part of judo, but only in pre-arranged forms (型, kata) and are not allowed in judo competition or free practice (乱取り, randori).
The philosophy and subsequent pedagogy developed for judo became the model for other modern Japanese martial arts that developed from koryū (古流, "traditional schools"). The worldwide spread of judo has led to the development of a number of offshoots such as Sambo and Brazilian jiu-jitsu. Judo practitioners are called judoka.