Automobiles, sometimes called cars, are four-wheeled motor vehicles designed primarily for passenger transportation and powered by an internal combustion engine, most often fueled with gasoline (a liquid petroleum product). Throughout the world automobiles represent one of the greatest of modern technology’s accomplishments. They are manufactured in large numbers by the world’s largest industry and rely on a broad range of new technologies for design, production, and performance.
The automobile was a force for change in twentieth-century America. It provided the basis for a consumer goods society, and it gave rise to ancillary industries that revolutionized the steel and petroleum industries. It also brought a host of environmental problems, from air pollution to land use conflicts.
Although the automobile was first perfected in Germany and France toward the end of the nineteenth century by Gottlieb Wilhelm Daimler, Karl Benz, Emile Levassor, and Nicolaus Otto, it was Henry Ford who pushed the automobile into the mainstream of American life. His invention of the moving assembly line allowed him to reduce the cost of the Model T until it became affordable for middle-class families.
Automobiles are manufactured in a wide variety of sizes and shapes to meet the needs and preferences of many different types of people. They may have bodies made from metal, glass, or plastics; engines fueled by gasoline, diesel fuel, or kerosene; and various systems for safety and control. Some of these systems are mandated by law, such as seatbelts and airbags, while others, such as tire pressure monitoring and stability control, are optional.