The bicycle is a machine for transportation and recreation that is used worldwide by millions of people. It consists of two wheels, a frame, handlebars for steering, and pedals that are connected to the back wheel by a chain. The cyclist rides the bicycle by placing his or her feet on the pedals and pushing on them to move the rear wheel.

Pedaling is the most important and common method of cycling, although there are other ways to pedal a bike, including riding while sitting down or leaning forwards. Most modern bikes are designed to be comfortable and to allow the rider to pedal efficiently and without injury.

Bicycles have become increasingly popular in countries around the world for their health and environmental benefits. Many cities have a network of bicycle routes and cycling schools for children.

Some researchers have found that the social side of cycling – talking and sharing experiences while you are out on your bike – is as good for your wellbeing as the exercise itself. A recent study by University of California researchers found that a group ride can release the hormone oxytocin, which can help to reduce stress and bolster immune function.

A bicycle is a light frame with two wire-spoked wheels in tandem, typically attached to a seat and handlebars for steering. Depending on the type of bicycle, it may have brakes or be electric powered (also called an electronic bike).

The first pedal-driven bicycle was invented in Paris in the late 1860s and was based on a velocipede de pedale, which had been around since the 18th century. There is no clear evidence of who first attached cranks to a front wheel, but the idea has been attributed to French metalworker Pierre Lallement.

During the 1860s, the velocipede was a popular sport, and velocipedes were built in many parts of Europe. During this period, Michaux was the most important manufacturer of pedal bicycles in France. In 1865, the brothers Rene and Aime Olivier pedaled a velocipede from Paris to Marseille, inspiring a surge of interest in the new sport.

Early pedal-driven bicycles were slow and uncomfortably cumbersome, but the advent of the chain drive in 1868 improved speed and comfort. The chain drive, which allowed the drive to be transferred to the non-steering rear wheel, reduced the amount of force required for pedaling and made turning easier.

By the 1970s, a boom of interest in bicycles among young consumers was creating demand for 10-speed models, which offered increased gear ratios. These bicycles also became more durable and affordable, allowing more consumers to afford them.

In the mid-1970s, a worldwide recession caused a collapse in many bicycle manufacturers and a decline in sales. This created a vacuum that was filled by Japanese and Taiwanese companies, which reorganized and expanded to become major players in the bicycle industry.

Today, most bicycles are built from lightweight aluminum, steel, or titanium. They can be ridden by children and adults, both males and females, and are popular for recreational and athletic use as well as for transportation. The bike market is a highly competitive one, with hundreds of manufacturers competing for consumer dollars.