Boardsports are active outdoor sports that are played with some sort of board as the primary equipment. These sports take place on a variety of terrain, from paved flat-ground and snow-covered hills to water and air. Most boardsports are considered action sports or extreme sports, and thus often appeal to youth. Some board sports were marginalized in the past. However, many board sports are gaining mainstream recognition, and with this recognition have enjoyed wider broadcast, sponsorship and inclusion in institutional sporting events, including the Olympic Games. Surfing is the first known boardsport, originating from Polynesian culture. Skateboarding was then invented by surfers looking to "surf" on land. It is hard to estimate when most boardsports were "invented" because people have been making homemade versions throughout history. For example, it is not hard to conceive of a person, who is familiar with the concept of skiing or sledding, standing sideways on a plank of wood and riding down a snow-covered slope. M.J. "Jack" Burchett is credited with first doing this in 1929, using horse reins and clothesline to secure his feet on the plank of wood. Most boardsports have similar, equally unknown origins. Using data collected in the past decade, it is estimated there are 18-50 million skateboarders, 5-25 million surfers, and 10-20 million snowboarders in the world. Approximately 100 million people participate in boardsports worldwide. Classifications There are a variety of board sports, which are characterized by terrain: Surf, Snow, Wake, Skate are the primary. Water Surfing The grandfather of all board sports, is a surface water sport that involves the participant being carried by a breaking wave. Stand Up Paddle Surfing (SUP)A variant of surfing where one always a stands up on the board and propels oneself by a one-bladed paddle, without lying down on the board. Although originally the goal was to catch and surf the waves, a racing modality has emerged with similarities to kayaking. Skimboarding (1930s) A discipline of surfing involving riding a board on wet sand or shallow water. A predominantly recreational activity that has evolved into a highly competitive water sport. Windsurfing (1970) Also known as sailboarding. A water sport involving travel over water on a small 2–4.7 metre board powered by wind acting on a single sail. The sail is connected to the board by a flexible joint Bodyboarding (1971) Wave riding consisting of a small, roughly rectangular piece of foam, shaped to