An automobile, or motor car, is a self-propelled vehicle used for travel on land. It may be designed to carry a passenger or a limited amount of cargo. It is designed to be driven by human power, a gasoline or diesel-powered engine, or an electric motor.

Automobiles have revolutionized the world of industry and technology as well as everyday life in the United States and around the globe. They have given millions of people more personal freedom to go where they want and when they want. They have also created new jobs and industries. Millions of Americans work in factories that produce cars and millions more in restaurants or motels where travelers stop to refuel and rest. And, despite the fact that millions of people die in automobile accidents each year, they provide one of the main forms of transportation in most parts of the world.

The first automobiles were powered by steam, electricity or petroleum (gasoline). In the late 1600s Dutch engineer Christiaan Huygens developed a three-wheeled, steam-driven carriage with an internal combustion engine that ran on gunpowder. A Frenchman, Nicolas Joseph Cugnot, built a similar machine in 1789. These early machines were heavy and slow, but they laid the groundwork for future developments.

By the early 1900s, automakers had developed the assembly line, making it possible to manufacture large numbers of vehicles at low cost. Henry Ford innovated the mass production techniques that led to his Model T runabout, which sold for $575 in 1912—less than the average annual wage at the time. The automobile became a popular consumer product, encouraging family vacations to rediscover pristine landscapes and giving urban dwellers access to rural shopping centers. It also facilitated more relaxed sexual attitudes and provided teenagers with a way to experience freedom from parental supervision.

Eventually, the automobile became the backbone of a consumer goods-oriented economy. It ranked as the number-one source of industrial production in America, and by 1980, 87.2 percent of American households owned at least one motor vehicle. It prompted the development of new roads, improved highway systems and a host of ancillary industries that produced such things as petroleum and gasoline, rubber and later plastics. Those demands helped to fuel a new economic boom, which ended when the forces of progress that had once been fueled by the automobile began to wane in favor of more electronic media and other devices that have changed our lives forever.