Motocross

Motocross (often shortened to MX or MotoX) is a form of motorcycle sport or all-terrain vehicle, and traces its origins to British Scrambling competitions. The name "motocross" is a contraction derived from the words "Motorcycle" and "Cross Country". racing held on enclosed off-road circuits.

Freestyle motocross

Is a relatively new sport, is not racing and instead concentrates on performing acrobatic stunts while jumping motocross bikes. The winner is chosen by a group of judges. The riders are scored on style, level of trick difficulty, best use of the course, and frequently crowd reactions as well.
One stunt performed is the backflip, which was disputedly completed on a 250cc motorcycle by Carey Hart using a specially designed dirt ramp. Soon after this, Mike Metzger completed this stunt using a standard freestyle ramp and dirt landing . More recently Mike Metzger actually did a Backflip over the Caesar's Palace Fountains . Some consider the body varial 360 as the most difficult stunt being performed at this time. This stunt, also called the Carolla, was first performed by Chuck Carothers at the 2004 X Games. Prior to this, the backflip 360, or off-axis backflip, was widely considered the most challenging stunt. Another rider taking freestyle to a new level is Travis Pastrana. In 2006 he did the world's first double backflip, at the 2006 X Games Travis performed the world's first double backflip (in competition) . It earned him the gold for best trick, that is now considered the most difficult trick.