American Butokukan is a progressive, eclectic martial art system incorporating concepts and principles from several ancient combative styles, including principally:
Karate; which has taken many forms in several Asian societies. Evolving from the simplifying of Chinese martial arts, in Korea it became Tang Soo Do (way of Tang Dynasty hand) and Tae Kwon Do (way of foot and fist), and evolved in Okinawa from Okinawate (Okinawa hand) to Karate (first written using the character for China, translating to China hand, and later using the character for empty, translating to empty hand) and eventually becoming such arts as Shurite (Shuri hand, later splitting into Shuri Ryu and Shorin Ryu) and Shotokan (Shoto's institute), among others. Karate developed primarily during the 17th through 20th centuries, and was taken to Japan in the very early 1900s. We simply use the word karate to describe our art. It is typically characterized by rigid, linear punching and kicking techniques made effective through body conditioning and applying proper musculoskeletal alignment.
Aikido; which was most recently formalized around 1945 in Japan. Aikido is a distillate of jujutsu (unarmed wrestling and striking techniques) and kenjutsu (sword fighting), with its primary technical roots in the Daito Ryu school of jujutsu. Aikido emphasizes a blending of forces by which the practitioner unbalances an attacker and controls the direction and degree of applied forces. Students study time-space relationships and biomechanics, as well as how to safely take falls.