An automobile is a motorized vehicle designed for transporting people. It is usually powered by an internal combustion engine fueled by a volatile fuel such as gasoline or diesel. Modern automobiles are complex technical systems with subsystems that perform various design functions. Some of these subsystems have evolved from breakthroughs in existing technology; others are based on new technologies such as electronic computers and high-strength plastics or alloys of steel and nonferrous metals.

The basic concept of the automobile goes back several hundred years. Christiaan Huygens invented a type of steam engine fueled by gunpowder in the late 1600s. This invention inspired other scientists to develop the internal combustion engine that made gasoline-powered automobiles possible by 1900. Early steam engines could achieve very high speeds but were difficult to start and required frequent refueling. Battery-powered electric cars were more practical but had a limited range and were hard to find places to recharge them. Gasoline-fueled automobiles are the most common today, but they are also available as hybrids and electric vehicles that use alternative energy to run their engines.

Automobiles have become the dominant mode of transportation in the world and have dramatically changed the way people live. They are an essential part of the global economy, providing jobs and facilitating trade. They can also be a source of personal freedom by allowing people to travel to and from work or school on their own. However, they can be dangerous if they are driven recklessly, causing accidents that often lead to injuries or death. They also contribute to environmental problems by releasing carbon dioxide, a greenhouse gas, into the atmosphere. Many people, especially in urban areas, are dependent on automobiles for getting around. This can result in traffic congestion and air pollution. Moreover, the cost of owning and maintaining an automobile can be expensive.

Although the automobile was developed primarily in America, it has had a major impact worldwide. By the 1920s, it had revolutionized society and became a major consumer goods industry. It is also one of the major consumers of petroleum and steel, driving the economies of many ancillary industries. It is a significant force in the global environment, contributing to climate change and habitat destruction.

In the United States, automobile production began to plateau in the 1930s because of market saturation and declining technological innovation. However, some innovative models emerged, such as the Model T, which allowed a large number of people to buy a car for an affordable price. In the postwar era, engineering was subordinated to questionable aesthetics and to the pursuit of high profits from fuel-guzzling road cruisers, resulting in poorer quality, increased accidents and safety risks, and environmental damage.

The automobile has had a profound impact on world history, affecting every aspect of life from the way we live to the way we shop. It has shaped public policies, including those related to safety, pollution control, and the growth of cities. The automobile has also had a profound effect on the economy of countries, changing their patterns of development and increasing urbanization.