Currently, Shotokan recognizes 26 memorized forms, or kata. Until a student reaches the brown belt stage, one new kata should be learned for each successive kyu (not sub colour belts) exam, beginning with Heian Shodan for the 8th kyu exam. By the time a student tests for brown belt, that student should know all five Heians, plus Tekki Shodan. For the black belt exam, a student needs to also know Bassai Dai, Jion and Kanku Dai. Approximately three Kata's are then learnt for every Dan graded, although most serious karateka will know several more kata's than required.