The Sport of Jūdō 柔道

Jūdō (柔道), literally "gentle way" is a martial art founded in Japan by Kanō Jigorō (嘉納 治五郎) in the late 19th century. It mainly involves throwing and subduing one's opponent. Striking and weapon defenses are also taught, but these aren't used in competition or sparring.

Judo has evolved much over the years and is now an Olympic sport (my aunt was once in the Olympic judo team!). A referee judges the match and makes all scoring and penalty calls. If needed, he will call "sonomama" which means "do not move" and may discuss some element of the match. He will then call "yoshi" which will restart the match.

The object of a judo match is to score one point, or ippon (一本). This can be scored immediately by throwing your opponent on his or her back, or by subduing your opponent with a choke or armlock. It can also be scored if you keep your opponent on the mat off his or her feet for 25 or more seconds.

A waza-ari counts as half a point and is awarded for a throw that does not have quite enough power or control to earn an ippon, or for keeping your opponent on the mat for 20 seconds.

A yuko is even lower than a waza-ari and is mostly used for tie-breaking. It is awarded for a hold of 15 seconds, or an even weaker throw. A waza-ari beats any number of yuko, but a waza-ari with yuko beats a waza-ari without yuko. No number of yuko can make an ippon.

The lowest score is a koka, and is only used when both players have equal waza-ari and yuko. One yuko beats any number of koka. A koka is scored for even weaker throws.

Penalties can be issued by the referee. The first is a warning, the second is a yuko for the opponent, the third is a waza-ari for the opponent, and the fourth is an automatic ippon for the opponent.