Wing Chun is a very efficient, simplified system of Chinese Kung Fu, originally created by a Shaolin grandmaster as a way to learn effective self-defence fast by focusing on priorities. It specialises in efficient blocking, parrying and counter striking, with secure, defensive footwork. When Bruce Lee was young, he considered it to be the perfect martial art.
Chi Sau (sticky hands)
Wing Chun arguably has the best training exercise of all systems of self-defence: Chi Sau (sticky hands).
Chi Sau is like Tai Chi’s Tui Shou (push hands) exercise, but with strikes included, and is generally done in a square-on neutral stance.
Although in his later years Bruce Lee focused mainly on refining his method of attack under the influences of fencing and boxing; he maintained “sticking” as his fundamental strategy for defence according to the Tao of Jeet Kune Do (which wasn’t officially published by him, but was a compilation of the notes found in his study after his death, some of which he may have held dearer than others, so we should keep an open mind on the topic).