a bicycle (or bike) is a small, human powered land vehicle with a seat, two wheels, two pedals, and a metal chain connected to cogs on the pedals and rear wheel. a frame gives the bike strength, and the other parts are attached to the frame. the name comes from these two words - the prefix "bi-" meaning two, and the suffix "-cycle" meaning wheel. it is powered by a person riding on top, who pushes the pedals around with his or her feet.