Wikipedia:
Mountainboarding
Mountainboarding, also known as Dirtboarding, Offroad Boarding, Grass Boarding, and All-Terrain Boarding (ATB), is a well established[1] if little-known extreme sport, derived from snowboarding. A mountainboard is made up of components including a deck, bindings to secure the rider to the deck, four wheels with pneumatic tires, and two steering mechanisms known as trucks. Mountainboarders, also known as riders, ride specifically designed boardercross tracks, slopestyle parks, grass hills, woodlands, gravel tracks, streets, skateparks, ski resorts, BMX courses and mountain bike trails. It is this ability to ride such a variety of terrain that makes mountainboarding different from other board sports.