Karate was a type of martial art which was developed in Japan on Earth from older Chinese martial art forms. It included poses and movements called katas or forms. Individuals who practiced karate could advance in rank depending on their level of training or expertise. Beginners started off as a "white belt", and could progress through other coloured belts, including brown, to become a "black belt". There were at least five different levels, or degrees, within the black belt rank.(TOS novel: Prime Directive, ST novel: A Singular Destiny)
This form of combat was extremely popular in the United States of America in the later 20th century[citation needed].
In the 20th century, Mas Oyama of the Kyokushin karate discipline developed a form called Tsuki No Kata. This particular form, or kata, could be translated as "punching form" or "fortune and luck form". (ST novel: A Singular Destiny)
Ryan Leslie trained in karate, as well as several other martial arts, as a young man. (TOS - Who's Who in Star Trek comic: "Issue 1")
In 2267, James T. Kirk used the fifth, ninth, and fourteenth katas on the planet Bavarya. (TOS novel: Mission to Horatius)
Pavel Chekov was also skilled in karate, which he claimed was invented in Russia before being stolen by the Chinese. (TOS novel: Prime Directive)
In the 24th century, the deputy security chief of the USS Budapest and Sam Bowers practiced karate. (ST novel: A Singular Destiny)