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
Judo in the United States the U.S. development of judo is Yamashita Yoshitsugu, who came to the U.S. in 1902 in order to teach judo to the Japanese community. Yoshiaki ended up teaching Senator James Wolcott Wadsworth Jr.'s wife, who happened to attend the same country club as Theodore Roosevelt. Mrs. Wadsworth told Roosevelt about judo, and he became interested in the sport. Yoshiaki was subsequently invited to Washington to give a demonstration at the White House. There was a contest with a wrestler by the name of John Graft, who was the coach at the U.S. Naval Academy and who was teaching President Roosevelt