A bicycle is a two-wheeled human-powered vehicle that is propelled by pedals and steered with handlebars. It is widely used for recreation, transport and exercise. It is the most efficient means of human transport for its size, and it can carry a rider at three times the speed of walking.
The bicycle was first developed in the early 19th century, although historians disagree about its exact origin. It is generally accepted that the first verifiable claim for a practically usable bicycle dates to 1817. It was designed by Karl von Drais Sauerbronn, a civil servant to the Grand Duke of Baden in Germany. He patented his Laufmaschine (German for “running machine”) in 1818, which was known as a draisine or velocipede (French for bicycle). It was also called a hobby horse, dandy horse, or dandy bike.
While there are many claims of who invented the bicycle, no individual can be credited with its invention as it was the result of the efforts of a number of people. Leonardo da Vinci is credited with drawing a bicycle in 1492, but the sketch was later determined to be a forgery. Da Vinci did, however, draw other, similar vehicles in his Codex Atlanticus, including a device that could be ridden like a bike but was not considered an ancestor of the modern bicycle.
Bicycles became a popular means of transportation around the world after being introduced in Europe. They allowed urban dwellers to commute from their crowded inner-city tenements to more spacious suburban dwellings, and they helped to relieve the burden on the city’s overtaxed horse populations. They provided a convenient way to travel for leisure, as they were faster and more energy efficient than walking.
By the turn of the 20th century, bicycles were commonplace in many areas, providing an affordable means of transport for millions of people. They reduced crowding on public transit and allowed commuters to save money by eliminating the need for taxis. They also enabled families to take vacations away from work and allowed people to visit relatives in far-away cities.
As technology improved, bicycles became lighter and more efficient, making them a popular mode of transportation. The development of alloy metals and hollow-section steel frames reduced weight and made the bikes easier to maneuver, while new tire types increased traction and efficiency. The introduction of the derailleur gear system and the chain drive (originated by Englishman James Starley) enabled bicycles to be driven at lower speeds without using cranks.
Modern bicycles come with a variety of accessories to enhance riding comfort and safety, including seats and handlebars that adjust for different riders, frame-mounted racks for transporting luggage and equipment, fenders to protect the biker and pedestrian from road debris, and lights and reflectors for use at night or in poor visibility. Bicyclists must wear a helmet and appropriate clothing to be safe on the road. Drivers should yield to cyclists and be extra vigilant when turning at intersections, driveways and parking lots.