. A skateboard is propelled by pushing with one foot while the other remains on the board, or by pumping one's legs in structures such as a pool or half pipe. A skateboard can also be used by simply standing on the deck while on a downward slope and allowing gravity to propel the board and rider. There is no governing body that declares any regulations on what constitutes a skateboard or the parts from which it's assembled. Historically, the design of the board has conformed both to contemporar… (More on Skateboards)