Martial arts have existed for almost as long as humanity has existed. Defined most simply as a combat-based fighting system, martial arts is a broad, sweeping term encompassing so-called Western martial arts like wrestling, boxing, and Savate and so-called Eastern martial arts like Karate, Kung Fu, Judo, and Muay Thai. However, earliest known martial arts regardless of its region of the world resemble wrestling and boxing (such as those used in the ancient Olympic games of Greece) and today blending of different martial art styles such as in Jeet Kune Do, American Kenpo, and Mixed Martial Arts make the distinction rather moot. Though, the term martial arts generally encompass in the mind of most people as the described Eastern forms, which will be the basis of this piece, it will be the term most often employed in this manner. That said, a number of early comic book heroes like Batman, Wildcat, and Captain America employed boxing, wrestling, and tumbling/acrobatics. Further, various early characters in mediums like comic strips, pulp novels, and serial radio programs like the Shadow, Green Hornet's Kato, and Mandrake the Magician's Hojo employed Eastern styles but they often were generalized (writers hearing of stuff like Karate and Kung Fu but knowing too little to describe them); such was the same with early comic book characters like the Sandman, Doctor Mid-Nite, and Captain Marvel's enemy Nippo (in the Silver Age, there was also others like Doctor Strange, Mandarin, Karate Kid, Peter Cannon – Thunderbolt, and Judomaster). Where martial arts became a point of interest in American comics generally line up with what was called the "Kung Fu craze."