Korean martial arts lacked a grading system up until the Japanese occupation (1910–1945) during which a variety of Japanese martial arts were introduced into the Korean school system, most notably judo, karate-do and kendo. After the occupation ended, newly emerging martial arts like taekwondo, tang soo do, soo bahk do and hapkido adopted the dan (단, 段) and (급, 級) ranks. The dan rank system is also used by "baduk" players. Nowadays, the Korea Taekkyon Association also issues dan ranks to "taekkyeon" practitioners.