Bicycles are human-powered vehicles, propelled by pedaling. They are an efficient form of transportation. The bicycle has been a major influence on human society. It has contributed to cultural and industrial advancement. Today, most people know how to ride a bicycle.

A bicycle’s frame and handlebars are made of stainless steel or aluminum alloy. In some cases, the seat posts are also made of steel or aluminum. Most bicycles use a chain to transmit power to the rear wheel. Some bikes, however, use shaft drive.

The front triangle of a bicycle contains the fork, the top tube, and the seatstay. A headset is attached to the fork to allow it to turn inside the head tube. This makes steering easier. Other components of a bicycle are the crankset and the wheel.

The crankset is the assembly of cranks, bearings, and axle. It is held in the axis by the bottom bracket. Pedal cranks transfer 99% of the power to the wheels. These components are usually hand-brazed, welded, or mechanically joined.

Handlebars are flat, raised, or dropped. The seat is generally steel, or it can be covered with cloth or nylon. Children’s bicycles may be fitted with streamers or cosmetic enhancements. Parents sometimes add a rear-mounted child seat.

The bicycle’s front wheel is normally a free-wheel. However, a very small number of bicycles are fitted with a shaft drive. Wheels are made by rolling steel strips into hoops or by welding them. They are then drilled to accept spokes.

A bicyclist must obey all traffic signs and signals. He or she should use a bell if riding at night. Also, bicyclists who are carrying children under one year old must be in an infant sling or properly affixed bicycle trailer. Those under 16 must wear a helmet that is fastened securely.

Cyclists should wear bright clothing for daytime rides. They should also exercise due care to avoid collisions. If riding at night, they should be sure to wear a red taillight. During daylight, they should use a white headlamp. Cycling is a great way to build up physical strength. When cycling, it is important to make eye contact with drivers. Occasionally, a door will open in the cyclist’s path.

Bicyclists may use a hitch to tow a trailer, but a bicycle’s capacity must not exceed its design. Bicyclists pulling onto a highway from a driveway must yield the right of way to vehicles and pedestrians. To do this, they should wait until a green light appears.

Before riding, it is recommended that the cyclist take some time to read the traffic laws and regulations in his or her area. The United States Department of Transportation has developed a set of guidelines for bicyclists. For example, they should not impede traffic by swerving to avoid obstacles, and they should leave three feet of space between themselves and parked cars.

The bike’s brakes must be used. Pedals must be stopped at stop signs and red lights. Additionally, bicycles must have a rear red reflector that is visible from 100 to 600 feet. There must also be a white front headlamp.