Dan (rank) highest level that might be attained, with instructor certification and judge/judgment authorization being understood as higher-level or more sophisticated. Many arts use between one and ten dan ranks: In some martial arts, black belts are worn for all "dan" grades. In others, the highest grade (10th "dan") wears a red colored belt. In Jūdo and Shotokan 6th to 8th "dan" may wear a red and white-patterned belt and 9th to 10th "dan" may wear a solid red belt. There is some variation even within styles. Generally, belts do not have markings that indicate the actual "dan" grade. Okinawan styles used
Rank in Judo are yet to attain that level and who hold grades. Those who hold "dan" grades are collectively termed (literally "person who has dan") and those with "kyū" grades are , literally "person without dan". This ranking system was introduced by Kanō Jigorō, the founder of judo, in 1883. However, the current system is not the original one, but based on Kanō's last system introduced between 1926-1931, with some modification shortly after Kanō's death in 1938. The first "dan" grades were awarded to his students Saigō Shirō and Tomita Tsunejirō. Since then it has been widely adopted by modern martial arts.