BMX

Sometime in the early 70's in California a group of kids started modifying their Schwinn bicycles (the 20" stingray being the first noted) and created a brand new sport. These kids where recorded by Bruce Brown in his film On Any Sunday, spreading the word of this sport across the US. The original name was Bicycle Motocross and was shortened down to BMX. This video had an impact on thousands of kids in that summer, many of whom could be seen riding these modified bike trying to emulate their motocross heroes.
BMX is very similar to it's predecessor motocross in many ways. It also is very different in the technicallity of the tricks and the speeds in which they are delivered. There are many tricks that could never be done in motocross that can be performed on these bikes. In 1982 the movie E.T. showed several kids on BMX bicycles helping to increase the popularity of the sport. At this time many BMX riders where starting to merge skate park riding with more elaborate and technical tricks creating what is known today as "freestyle BMX".
In the early 90's many "extreme sports" blew up BMX being one of these. In 1995 at the first X-Games in Rhode Island BMX had its very own competition series which helped to bring the sport into the mainstream as being a legitimate and excepted career.