JKA Hangetsu (41 moves) by Naka Sensei

It is said that Sokon Matsumura learned this kata during one of his journeys to China. Like many Shotokan kata, Hangetsu can be found in other styles of karate as well, and with several variations.
Hangetsu is a very unique kata within the Shotokan system. It is an internal kata, focusing on the
cultivation and release of ki energy, or one's inner force.

The JKA version has 41 counts. Other styles of karate tend to use the kata's original name of Seisan
(or Seishan), which means "13". Some say the number 13 refers to the original number of steps of
the kata, others believe it refers to the number of different techniques found in the kata. Gichin Funakoshi changed the kata's name to Hangetsu, meaning "Half-Moon," describing the semi-circular
movements of the hands and feet during the kata's beginning sequence. Although many kata have
these same circular movements (i.e. step in zenkutsu-dachi), the half-moon sliding motions of the
feet tend to be a little larger and more pronounced when performing hangetsu stance. The half-moon
shape is also seen at the end of the kata, with the leg and hand movements during the uraken-uchi,
and of course, with the mikazuki-geri.