Practitioners of Shotokan Karate often place high importance on the analysis and performance of Kata. Kata are a pre-determined series of movements executed against imaginary opponents. performing kata Originally, Kata were used to train the basic techniques and then eventually the application of those techniques. These days, Kata has become more of a performance art and is heavily exploited in martial arts competitions.
In the Shotokan system, there are essentially 26 mainstream kata, each with differing levels of difficulty and applications. Some organisations have another very basic kata called "Kihon Kata" or "Taikyoku Shodan" used to help teach beginners. There is, however, some debate on the usefulness of this basic kata since Heian Shodan is not that much more difficult technically, thus is just as easy to learn. Other styles, notably Shukokai and some forms of Goju-ryu include a series of Kata (Fukyukata and Shiho-uke) specifically designed to teach children. Hirokazu Kanazawa has created or adapted a few additional kata in the SKIF/SKKIF organisation, such as Gankaku-Sho (adapted from a Tomari-te Shorin-Ryu version of Chinto), and has reintegrated a few from other Okinawan styles, such as the kata Seinchin and Seipai.
While the origins of most of the Kata are obscure, many show distinct similarities to others. There are indeed a few in the list which all seem to share the same origins in China. Others are purely Okinawan inventions, while others are adapted from other styles.
A Non-Exhaustive List of Shotokan Kata
(This is non-exhaustive, because of the introduction of new or adapted Kata in the SKIF and JKS systems)
Kihon Kata / Taikyoku Shodan (not used/taught in all organisations)
Heian Shodan (same origins as Goju/Shito-ryu Pinan Nidan)
Heian Nidan (same origins as Goju/Shito-ryu Pinan Shodan)
Heian Sandan (same origins as Goju/Shito-ryu Pinan Sandan)
Heian Yondan (same origins as Goju/Shito-ryu Pinan Yondan)
Heian Godan (same origins as Goju/Shito-ryu Pinan Godan)
Tekki Shodan (adapted from Naihanchi by G. Funakoshi)
Bassai Dai (developed from Passai)
Kanku Dai (developed from Kushanku)
Jion (one of the "jion group" originating from Tomari-te with roots in Chinese Boxing)
Empi (developed from Wansu)
Jiin (one of the "jion group" originating from Tomari-te with roots in Chinese Boxing - this kata is no longer taught in JKA syllabus)
Jitte (one of the "jion group" originating from Tomari-te with roots in Chinese Boxing - contains several useful applications against a bo)
Sochin ("tranquil force", derrived from Naha-te and Shito-ryu. Introduced into Shotokan by Yoshitaka Funakoshi)
Gankaku (derrived from Chinto)
Nijushiho (thought to originate from one of the chinese Dragon styles; named 'niseishi' in okinawan styles, and introduced to Japan by G. Funakoshi, changing the name to 'nijushiho')
Meikyo (derrived from three original kata called Rohai shodan, nidan and sandan, and introduced into Shotokan by G. Funakoshi.
Tekki Nidan (like Tekki Shodan, derrived from Naihanchi)
Tekki Sandan (like Tekki Shodan and Nidan, derrived from Naihanchi)
Gojushiho Dai (one of two forms with the same embusen, originally adapted from the Shorin-ryu kata Useishi or Gojushiho)
Gojushiho Sho (second of the two Gojushiho Forms -- see note below*)
Other Introduced or Adapted Kata
Gankaku Sho (Tomari-te Shorin-ryu Chinto, introduced into SKIF by Hirokazu Kanazawa)
Nijuhachiho (Adapted from Shito-ryu Nipaipo, introduced into SKIF by Hirokazu Kanazawa)
Seinchin (Almost entirely unchanged from Shito-ryu/Goju-ryu, introduced into SKIF by Hirokazu Kanazawa)
Seipai (Introduced into SKIF by Hirokazu Kanazawa)
Hyakuhachiho (Adapted and modified from the Shito-ryu/Shuri-te kata "suparempei", introduced into JKS by Tetsushiko Asai)
** Note about "Gojushiho-Dai" and "Gojushiho-Sho": Just as an interesting anecdotal story, the original naming of these two kata were as follows: The form making use of neiko-ashi-dachi (cat leg stance), and keito-uke with sanbon ippon-ken nukite (chiken-head block and triple one-fingered strike) was originally "Sho" whereas the the form making use of sanbon nukite (triple spear-hand strike) was "Dai". The story goes along the lines of a high-ranking JKA instructor, during a competition, announced Gojushiho-Dai, but then performed Gojushiho-Sho. Due to his high rank, nobody questioned him about it, and as a result all schools/organisations originating from the JKA use the reversed names. Organisations associated with or derrived from Hirokazu Kanazaw's Shotokan Karate-Do International Federation (SKIF) keep the original Dai and Sho names, because (it has been said) that Kanazawa was a higher ranked instructor at the time, and refuses to change the names from the original.