Bicycle

A bicycle is a human-powered or motor-assisted, pedal-driven, single-track vehicle with two wheels attached to a frame, one behind the other, ridden by a person called a cyclist. Baron Karl von Drais introduced the two-wheeled dandy horse, or draisine, in Germany in 1817 and 1818, a pedal-less machine propelled by pushing the feet against the ground; French inventors Pierre Michaux and Pierre Lallement added cranks and pedals to an enlarged front wheel in the 1860s to create the velocipede, the first mass-produced bicycle design, and wire-spoke wheels, patented in 1869, led to the tall penny-farthing. J.K. Starley's Rover, built in Coventry, England and introduced in 1885, is usually described as the first recognizably modern bicycle, with a chain drive connecting the pedal cranks to the rear wheel, and John Boyd Dunlop's 1888 pneumatic tire greatly improved comfort and performance. More than a billion bicycles exist worldwide, with China's Flying Pigeon model alone accounting for roughly 500 million units produced, and the bicycle is widely described as the most common vehicle of any kind on Earth, used for transportation, recreation, fitness and competitive sport.