The bicycle is a two-wheeled, human-powered mode of personal transportation that transforms muscle power with chain-driven gears into motive force. Numbering perhaps one billion today, bicycles and analogous tricycle rickshaws accomplish a significant component of the world's commuting and light transport. Bicycle ownership and use is globally very uneven. Western European countries have the most bikes per capita, and in the Netherlands [Page 115]and Denmark, as many as one-third of commuting trips are by bicycle. Japan, Australia, and the United States have about the same number of bicycles per capita, but Japanese commuters use bicycles far more. In some south and southeast Asian cities rickshaws haul more goods and passengers than motorized vehicles. The world's preeminent cycling society is China, with at least 300 million ...