Sumo (also known as Ozumo or Sumo wrestling), is a competition contact sport wherein two wrestlers (or rikishi) face off in a circular area. The sport is of Japanese origin and is surrounded by many rituals. The Japanese consider Sumo a gendai budo: a modern Japanese martial art.
The Sumo tradition is very ancient, and even today the sport includes many ritual elements from when Sumo was used in the Shinto religion.