Taekwondo (태권도) or Tang Soo Do (당수도) is a Korean fighting style created by Korean students who developed it from Northern Chinese Kungfu (功夫) during Tang dynasty era (618-907).
Modern Taekwondo name was created by Choi Hong Hi in 1955, this new name is more popular and used worldwide.
Taekkyon (태껸) is a Korean fighting style created by warriors of the Silla Dynasty (57 BCE - 935 CE), also known as Taekkyeon and Taekyun.
Taekkyon focus on kicks because using the leg provide better reach and superior striking power for skinny - tall ancient Korean people (weaker punching power but longer kicking range).