Skateboarding

Skateboarding
Uses a board mounted on wheels, and often ridden on a "half-pipe" or in urban settings. Some of the most famous skateboarders, and early pioneers of the sport are Rodney Mullen and Tony Hawk.

Snowboarding
A cross between skateboarding and skiing, the board medium is snow, although the condition of the snow can have a major impact on snowboarding style and technique. The four subcategories are freeride, freestyle, alpine and powder.

Sandboarding
A recreational activity similar to snowboarding that takes place on sand dunes rather than snow-covered hills.

Street Luge
Street luge is an extreme gravity-powered activity that involves riding a streetluge board (sometimes referred to as a sled) down a paved road or course. Street luge is also known as land luge or road luge. Like skateboarding, street luge is often done for sport and for recreation.

Longboarding
A longboard is a surfing variant of a skateboard, similar and related to a surfboard or snowboard with wheels. It is used for cruising, downhill racing, slalom racing, sliding, and/or transport. However, most stunts, and the boards themselves are very different from that of a typical skateboard. They usually are designed for the descent of a hill, slides, carves, manual or "dancing" with the board.
Source: Wikipedia