A bicycle, also known as a bicycle or pedal cycle, is a motor-driven or pedal-controlled, single wheeled, two-wheeled vehicle, with two pedals attached to a rigid frame, on which the rider rides. A bicycle rider is often known as a bicycle rider, or bicycle racer. Bicyclists can be children, teenagers, adults, and even professionals. In the United States, bicycle riding is a popular recreational activity, particularly on busy highways and urban streets.

The first bicycles were invented about five hundred years ago in Italy. At that time, the two-wheeled design was developed to provide more efficient transportation than the one-wheeled design. By around the late nineteenth century, most bicycles had a freewheel on the front wheel and the back wheel was linked to a single chain. Many cyclists used bicycles with between twelve and fifteen gears. Other bicycle designs have different gears, but some bicycles still use a freewheel.

Bicycle designers Thomas Keller and Rudiger Aldrich developed the first velocipedes in 1890. These early velocipeds did not have a front wheel. They were referred to as “velocipedes,” which in the German language translates to “winged ones.” Velocipedes are similar to modern day tricycles, in that they have a saddle on the rear wheel and a back wheel that works together. However, there are major differences in the way a bicycle is powered.

Unlike modern bicycles, velocipedes had no pedals. The rider would “drive” the bicycle by pushing against the back tire with his feet. There are several different designs for this type of bicycle, such as a three-step pedal, a step-by-step pedal or a single-step pedal. A single step pedal allows the cyclist to go up a hill without putting pressure on the back tire. Two-wheel-drive velocipedes are similar to the tricycles and can be ridden up steep climbs.

There are two-wheeled bicycles that closely resemble tricycles, including the double-sided bicycle and the chaise du velomeur. A double-sided bicycle has a back wheel that can be moved left or right to change direction. A chaise du velomeur is similar to the bicycle described above except that it has a seat attached to the back. Some bicycles that closely resemble velocipeds are the steel-framed steel bike and the steel monorail.

The nineteenth century witnessed a resurgence of bicycle design. This movement, which resulted in the development of the bicycle with its many variations, led to the development of new technology and new styles. During this period, the first mass production of bicycles began. The most popular of these bicycles were windlasses. Windlasses are now among the most commonly used bicycles in the world.