Skateboarding is the act of riding and performing tricks using a skateboard. A person who skateboards is most often referred to a skateboarder, skater or skate rat. Skateboarding can be a recreational activity, an artform, a job, or a method of transportation. Skateboarding has been shaped and influenced by many skateboarders throughout the years. A 2002 report by American Sports Data found that there were 18.5 million skateboarders in the world. 85 percent of skateboarders polled who had used a board in the last year were under the age of 18, and 74 percent were male. Skateboarding is relatively modern. A key skateboarding maneuver, the ollie, was developed in the late 1970s by Alan "Ollie" Gelfand as a half-pipe maneuver. Freestyle skateboarder Rodney Mullen was the first to take i...more >>t to flat ground and later invented the kickflip and its variations.