Automobiles are four-wheeled vehicles that are used for passenger transportation and powered by an internal combustion engine using a volatile fuel. They were introduced in the early 20th century, and are now one of the most common means of personal transportation worldwide, especially in cities and small towns where public transportation is not available. Trucks, buses, limousines and trains are also automobiles, although they have more wheels than a typical car and use different engines.
Before the development of modern automobiles, human beings traveled by foot, horseback or on the backs of others’ animals. Some of the first automobiles were steam engines attached to wagons in the late 18th century, but they were slow and laborious. The invention of the internal combustion engine, which exploded fuel inside a cylinder to push a piston down and turn the wheels, led to the development of much faster and more maneuverable cars.
By the early 1900s, many Americans could afford to own automobiles. The nation’s vast land area, large population and relatively equitable income distribution meant a great demand for transportation. In addition, cheap raw materials and the American manufacturing tradition of standardized products encouraged mass production. The resulting low unit prices allowed automobiles to be sold for less than the cost of a year’s wages.
In the 1920s, automobile technology advanced rapidly. American manufacturers like Ford Motor Company and General Motors produced automobiles of increasingly sophisticated design. European producers such as Mercedes-Benz and Rolls-Royce struggled to match this new level of performance while keeping their cars affordable to middle-class buyers.
Today, automobiles are used almost everywhere in the world and are among the most widely owned consumer goods. They help people to get to work and school and to visit friends and family, and they allow people to go shopping and see places of interest that are far away. However, they also cause traffic congestion and pollution when too many people try to drive them at the same time, and they can lead to accidents if drivers aren’t careful.
To make cars safer, government regulations require that they have seat belts and airbags for passengers and drivers. Other safety features include brakes that work by friction, allowing the car to stop quickly in an emergency, and regenerative brakes that turn some of the energy from the motion of the car into electricity to recharge the batteries. In addition, most countries require that all people in an automobile wear seat belts and that children ride in child seats. The industry is dominated by several large corporations. The biggest are Toyota and Ford, with General Motors a close third. A few smaller companies have achieved reputations for excellence or have made significant technological advances. In addition, there are hundreds of automobile models available for purchase. Some are aimed at economy, while others are designed for style and comfort. Some cars offer all-wheel drive, which is useful in snowy or rainy conditions. Others have a rearview mirror to help the driver keep track of approaching obstacles.