A self-propelled vehicle for transportation on land that is powered by an internal combustion engine and can seat two or more people. Also called motor car, motor vehicle, and automobile (from French l’automobile, literally “self-moving carriage”). Automobiles are part of the branch of engineering known as automotive engineering.

The automobile was a major force in the transformation of modern society. It became almost inconceivable, or at least highly inconvenient, to live without one. In the United States alone, the automobile now carries more than three trillion miles per year. Its impact extends from the reorganization of cities to the flexible distribution of goods by trucks. Entire societies, especially those of industrialized nations, have come to be structured around the power of rapid long-distance movement conferred by the automobile.

Automobiles have revolutionized social and economic life, but they also bring their own problems. Automobiles create dependence on fossil fuels and produce significant amounts of pollution. In addition, their design and operation are often unsafe.

During the late nineteenth century, many European manufacturers developed sophisticated passenger cars based on the steam and gas engines of the locomotive. But the American automobile industry won the day. Cheap raw materials, a tradition of mechanization in production, and the absence of tariff barriers encouraged large-volume sales throughout the nation and the world.

By 1920, the gasoline-powered automobile had overtaken Europe’s streets and highways. At the same time, Henry Ford innovated mass production methods to reduce the price of his Model T runabout until it became affordable for middle-class families.

As the twentieth century progressed, the automobile continued to expand its dominance in the United States and most other countries. The era of annually redesigned, mass-produced autos reached its height during the Great Depression, and by 1935 market saturation had occurred. To maintain unit sales, automakers instituted annual model-year changes in order to keep consumers buying new vehicles.

Automobiles require a complex interplay of systems that control and operate them. The engine (which burns gasoline or other fuel), transmission, wheels and tires, suspension, steering system, braking system, electrical system, cooling and lubrication systems are all essential components that must work together. The autos are governed by rules and regulations that control safety, emissions, and energy consumption.

Some of the benefits of owning an automobile include greater convenience, the ability to travel more quickly and far from home, and improved social connections with friends and family. However, automobiles can increase the risk of injury or death in accidents and can result in high operating costs, including gas and maintenance costs. In some cases, it may be cheaper to use public transportation, although this can also be inconvenient and unreliable. The automobile has also brought its own problems, including the degradation of landscapes and urban sprawl, traffic congestion and air pollution, as well as increased health care costs for drivers and passengers. For these reasons, it is important to consider the pros and cons of owning an automobile.