Jeet Kune Do is a hybrid martial arts system and life philosophy founded by world renowned martial artist and actor Bruce Lee in 1967.
In 2004, the Bruce Lee Foundation decided to use the name Jun Fan Jeet Kune Do (振藩截拳道) to refer to the martial arts system that Lee founded. "Jun Fan" was Lee's Chinese given name.
The system works on the use of different 'tools' for different situations, broken down into ranges - Kicking, Punching, Trapping, and Grappling - with techniques flowing smoothly between them. It is referred to as a "style without style." Unlike traditional martial arts, Jeet Kune Do is not fixed or patterned and is a philosophy with guiding thoughts.
The core concepts of Jeet Kune Do are derived from Wing Chun. This includes such ideas as centerline control, punching with a vertical fist, trapping, and forward pressure. Through his personal research and readings, Lee also incorporated ideas from boxing and fencing. Later during the development of Jeet Kune Do, he would expand it to include the art for personal development, not just to become a better fighter.
One of the theories of Jeet Kune Do is that a fighter should do whatever is necessary to defend himself, regardless of where the techniques come from. One of Lee's goals in Jeet Kune Do was to break down what he claimed were limiting factors in traditional martial arts training and seek a fighting thesis which he believed could only be found within the reality of a fight. Jeet Kune Do is currently seen as the genesis of the modern state of hybrid martial arts.