Judo is a contact sport where players or judokas try
to pin someone on their back for 30 seconds. This
is called an ippon. A match is also won by making one person submit
by using an armlock or stranglehold. A
referee and two judges control the match and award points for throws,
holds, and moves. Judokas lose points if they foul. It is forbidden to
step on the opponent's face, pull down an opponent, or throw an opponent
by entwining a leg around the opponent's leg.