Sanda or San Shou is a sport that originates from China and is similar to Muay Thai and Kickboxing because it also involves punching, kicking and knee strikes. What separates San Da is that it also involves throwing techniques, takedowns and sweeps making it a great stand up art that is very suitable striking base for Mixed Martial Arts.
It’s the amalgamation and combination of these different fighting skills that have always distinguished Chinese styles.
A polished Sanda fighter must be able to display strong kicking and striking techniques and be able to apply throws, sweeps and takedowns quickly and efficiently.
This fighting style incorporates the following elements:
1. Ti –Kicking
2. Da - Striking
3. Shuai - Throwing
As far as I found out Sanda was originally developed by the Chinese military based upon the study and practices of traditional Kung Fu and modern combat fighting techniques. Sanda, in simple words, is face-to-face fighting with bare hands between two people, consisting of offensive and defensive effect and requires kicking at distance, pouching at stride distance and take-down throws when close.
You can find some general information at Wikipedia (http://en.wikipedia.org/wiki/Sanshou) and detailed information about it on the International Kickboxing Federation (http://www.ikfkickboxing.com/SanShouRules.htm).