Bicycle

A bicycle, often called a bike or cycle, is a human-powered, pedal-driven, single-track vehicle, having two wheels attached to a frame, one behind the other. A bicycle rider is called a cyclist, or bicyclist.
Bicycles were introduced in the 19th century in Europe and, , more than a billion have been produced worldwide, twice as many as the number of automobiles that have been produced. They are the principal means of transportation in many regions. They also provide a popular form of recreation, and have been adapted for use as children's toys, general fitness, military and police applications, courier services, and bicycle racing.
The basic shape and configuration of a typical upright, or safety bicycle, has changed little since the first chain-driven model was developed around 1885. But many details have been improved, especially since the advent of modern materials and computer-aided design. These have allowed for a proliferation of specialized designs for many types of cycling.
The bicycle's invention has had an enormous effect on society, both in terms of culture and of advancing modern industrial methods. Several components that eventually played a key role in the development of the automobile were initially invented for use in the bicycle, including ball bearings, pneumatic tires, chain-driven sprockets, and tension-spoked wheels.Heitmann JA. The Automobile and American Life. McFarland, 2009, ISBN 0-7864-4013-9, pp. 11 and following
==Environmental impact==
One of the profound economic implications of bicycle use is that it liberates the user from oil consumption.(Ballantine, 1972) The bicycle is an inexpensive, fast, healthy and environmentally friendly mode of transport. Ivan Illich stated that bicycle use extended the usable physical environment for people, while alternatives such as cars and motorways degraded and confined people's environment and mobility.ILLICH, I. (1974). Energy and equity. New York, Harper & Row.
==See also==
* List of cycling topics
==References==
===Citations===
===Sources===
* 
==Further reading==
* Max Glaskin, Cycling Science: How Rider and Machine Work Together January 2013, University of Chicago Press, ISBN 9780226921877
* Raymond Huttier. Le roman de la bicyclette, du célérifère au vélo moderne. (Bicycle history) 139 p. illustré. Editions Susse, Paris. 1951.
==External links==
* Pedaling History Museum The world's largest bicycle museum
* A range of Traffic Advisory Leaflets produced by the UK Department for Transport covering cycling.
* A History of Bicycles and Other Cycles at the Canada Science and Technology Museum
Category:Transport & planning