Automobiles are motor vehicles designed to transport passengers. They are usually powered by internal combustion engines, most commonly using gasoline, a liquid petroleum product. They can be driven on roads, highways, and off-road tracks. They are often equipped with a range of driver comfort and safety features.

The automobile revolutionized transportation and society in the twentieth century. It became indispensable for urban and suburban living, allowing families to move easily between jobs and homes as well as to shop, visit friends, and pursue hobbies. It has become one of the most important industries in the world and continues to influence economic and social change.

Despite their many social and economic benefits, automobiles have also been a source of controversy and conflict. The rapid growth of the industry brought with it a rise in traffic congestion, air pollution, and accidents. Concerns about health effects, such as lung problems and carcinogens, have also led to calls for greater regulation of the industry.

Automakers developed new manufacturing methods, including assembly lines, to speed up production and lower prices. By the 1920s, the Ford, General Motors, and Chrysler corporations dominated the American automotive market. These companies funneled their resources to the military during World War II, and afterward automobile production surged in Europe and Japan as well to meet rising demand.

While the automobile revolutionized urban and suburban life, it had its most profound effects on rural America. Farmers could now travel to markets in towns, and their children had the opportunity to attend school in town. The emergence of automobiles prompted the expansion of agricultural and livestock production as well as dozens of related spin-off industries, such as those for vulcanized rubber and road construction.

The development of automobiles allowed people to live in places that were previously inaccessible, and they opened up a whole new world of possibilities for leisure activities. For instance, the ability to go on long distance trips by car encouraged families to rediscover pristine landscapes. Teenagers gained independence with the freedom of driving, and dating couples could enjoy a more intimate atmosphere.

However, as the automobile grew in popularity, some concerns began to surface, such as increased air pollution and a drain on dwindling world oil supplies. Even so, the automobile continued to grow in popularity and it now seems impossible for most people to imagine a modern life without one.