INventions of skateboards.

I have chosen the inventions of skateboards. Skateboards is a flat piece of wood with four wheels. it has a truck, a bushing and some bearings.The modern skateboard originated in California in the late 1970s.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. If we want to go down a pipe, vert or a bowl, we have to pressure the front part of the deck and the gravitational force will pull you down gaining speed for you to do tricks.If we want to do an ollie, or a leap, we have to pressure the back part of the deck and drag our front leg and drag it on the front part of the deck.