BMX Biking, which is similar to mountain biking, is a multi-faceted sport with many different disciplines. There are four major BMX concentrations park, vertical, trails, and flatlands. They each have their own rules and specifics which will be outlined in this article. Park riding is often done in standard skate parks, as BMX park riding takes a great amount of inspiration from skateboarding. Skate parks have all kinds of different obstacles and they can be made from wood, metal, or concrete, which makes them the perfect grounds for BMX riding as well. Depending on the type of obstacle, the riders style will change. Some of the most common obstacles one will see in a park include quarter pipes, spines, flat banks, walls, mini ramps, boxes, hips, and pyramids. All are used for different tricks, and in sanctioned com mangosteen petitions, the speed, skill, and fluidity of the trick is rated and judged to determine a points-based winner. Vertical riding, which is commonly called by its slang variant, vert, is an extreme form of BMX. The standard ramp consists of two half pipes that have been joined to form what looks like an expanded u shape. The record for the biggest ramp is the 27-foot tall X-Games big air ramp. This is the most dangerous form of BMX racing, and there are very few professionals who go into this discipline, or stay at it for a very long time. Matt Hoffman, who is probably one of the best known BMX vertical riders, has nearly lost his life on several attempts to set new records for height and speed. Trail riding involves dealing with huge mounds of dirt formed by compacting mud and is sometimes known as dirty jumping.