American Kickboxing
American Kickboxing has been influenced by a combination of Muay Thai, Boxing, and Karate. Kickboxing has only been around since the 60's in America. It allows punching and kicking your opponent. Other things such as knees, elbows, head butts, holding and striking, chokes, and striking an opponent while they are down are prohibited. The participants wear padded gloves and footgear, and must execute a certain number kicks above the belt per round. Matches are conducted in a big square ring that is roped, such as in boxing or WWE, vary in time of rounds and # of rounds. The Winner is determined by knockout, judge's decision, or a technical equivalent of the same.
Historical Notes
Full-contact fighting first appeared in January 1970 by Joe Lewis (Father of American Kickboxing). He staged his first fight with Greg Baines and knocked him out to become the first ever heavyweight champion.
Source
The basis for most of my information can be found at www.martial-way.com/