change the name of their art from Tang Soo Do and others to Taekwondo. Hwang Kee, however, did not desire to modify his art into a more generic form and rebelled against the change, something that brought him legal complications that caused him to move his family to the United States, where Tang Soo Do would continue to thrive. Later on, Hwang Kee was exposed to the ancient document Muyedobotongji, which depicted descriptions of ancient Korean martial arts such as Subak. Drawing inspiration from this document, and using his cross-training in Chinese Gung Fu, Okinawan Karate and Korean martial arts, he created the Chil Sung hyungs, a series of 7 hyungs and the Yuk Ro hyungs, a series of 6 hyungs, which brought back some of the combat elements of the ancient Subak art contained in the Muyedobotongji. Years later, Tang Soo Do would change its name to Soo Bahk Do (Way of the Striking Hand), however, both names are still in use by various associations and represent essentially the same martial art. Tang Soo Do sets itself apart from other arts by identifying as a traditional martial art solely interested in self-defense, eschewing sport-orientation. It consists mostly of striking techniques focused towards self-defense, but also features several stand-up grappling and joint-manipulation techniques in its ho sin sul (self defense) and il sook si dae ryun (one-step sparring) curriculums. Tang Soo Do has had a sizable impact on the martial arts world, as the first example of Korean martial arts seen in the West, where people like Chuck Norris introduced and popularized its most characteristic techniques, such as the spinning back kick, spinning hook kick and spinning back fist. Curtis Bush, Dennis Alexio and Hector Peña have all used Tang Soo Do to become kickboxing and full contact world champions, and martial arts action stars the likes of Chuck Norris, Cynthia Rothrock and Hwang Jang Lee have popularized the art in film, television and, through homages, in video games as well. Hapkido arts Though various forms of grappling have been known in Korea for generations, Hapkido is essentially a 20th-century development, based on Japanese Daitō-ryū Aiki-jūjutsu but incorporating Korean striking techniques. The foundation for Hapkido was established by Choi Yong Sul. Returning from Japan in 1946, Choi began teaching material reportedly taught to Choi by Sokaku Takeda. Choi called his style Yawara [柔], but modified the name to Hapki Yusul