Automobile, also car or motorcar, four-wheeled vehicle designed primarily for passenger transportation and propelled by an internal combustion engine fueled most often by gasoline (a liquid petroleum product). One of the world’s most widespread modern technologies, automobiles are complex technical systems with multiple subsystems designed for specific design functions. The underlying scientific and technological building blocks of the automobile date to the late 1800s, when German engineer Karl Benz developed the first practical gasoline-powered car.

By the 1920s, the automobile had become a symbol of mass personal mobility and was the driving force behind new consumer-oriented industries and activities such as restaurants, hotels, amusement parks, fast food chains, and gas stations. The industry ranked as the largest producer of consumer goods and provided one out of every six jobs in America. It also was a major user of industrial products such as steel and petroleum, and was an important source of revenue for government, which used the taxes it collected to provide social services and maintain roads.

In the early twentieth century, American businessman and engineer Henry Ford improved the manufacturing process by developing an assembly line, making it possible to produce cars more cheaply. His Model T was so affordable that it put passenger automobiles within the reach of middle class families. Other manufacturers followed suit, and by the 1930s car companies such as General Motors and Ford had dominated the automobile market.

The American automobile industry’s rise was aided by several factors, including its vast land area and the greater income distribution of the population than in Europe. Moreover, the absence of tariff barriers encouraged sales over a large geographic area. The American manufacturing tradition of assembling components and parts from separate sources also contributed to the industry’s growth.

Throughout the postwar era, the automobile industry focused on new designs and features. The increased unit profits resulting from such innovations as automatic transmissions and air conditioning were offset by the costs associated with high-polluting engines, a drain on dwindling world oil supplies, and environmental concerns over noise pollution and safety issues.

Today, automobiles continue to dominate global transportation, with an estimated 1.4 billion cars in operation worldwide. They are the principal means of travel for most people, allowing them to get around their communities, commute to work or school, and visit friends and family. In addition, many people use their cars to haul loads or to carry equipment.

Although many younger people are eschewing car ownership in favor of walking, riding public transit if available, or carpooling, the majority of Americans still consider a private vehicle an essential part of life. Besides offering freedom of movement and convenience, an automobile demonstrates to lenders that a person can make a regular payment, which in turn helps him or her to qualify for other loans such as mortgages and credit cards. Having a car also makes it easier to find employment and save money on commuting costs by living farther away from work.