The automobile is a four-wheeled motor vehicle designed for passenger transportation. It is propelled most often by an internal combustion engine fueled by a volatile fuel. It is considered to be one of the most significant inventions in modern history. It has shaped culture and society, brought many new jobs, industries and products to the world, and changed everyday life.
Automobiles were originally developed to transport people over long distances in comfort. Early cars used steam, electric power or gasoline as their energy source, with steam engines leading the way in Europe during the 1860s and ’70s. By the turn of the 20th century, however, gasoline-powered cars had taken over most road systems. In the United States, Henry Ford revolutionized production techniques with his assembly line; this reduced car prices until they were affordable to most middle-class families.
A modern automobile contains a complex technical system with numerous subsystems that must function together to achieve optimal performance. These include the engine, transmission, drivetrain, electrical systems, and suspension. The safety of passengers is a major concern. Modern vehicles have a high degree of safety built into their design, with features such as airbags and seat belts.
Modern automobiles are usually made of steel, although aluminum and other metals have been used as well. They have bodies that wrap around the mechanical parts, which are mounted on a frame. The body is usually molded and shaped to provide comfortable spaces for passengers, with windows and doors that allow them to view the scenery as they travel.
Today, most automobiles have at least two rows of seats and can carry up to nine passengers. They are typically equipped with air conditioning, heat and radios. Some have satellite navigation systems that allow drivers to find their destination and avoid traffic delays.
Automobiles have changed the world by giving people access to jobs, housing and leisure activities. They have also created a need for new roads and services such as gas stations and convenience stores. In addition, the exhaust from automobiles can cause pollution that harms the environment.
In addition to a wide variety of models, automobiles have many different styles. Sedans (called saloons in British English) have sloped rear windows and four doors; they are considered more formal than sportier coupes. Other types of cars include station wagons, minivans and passenger vans that combine the towing capacity of trucks with the passenger-carrying space of sedans; hatchbacks, which open up like trunks; and SUVs that are similar to sedans but have a raised back seat for additional cargo storage. Many automobile manufacturers began as other companies before moving into automotive production. For example, Toyota and Nissan both started as loom factories before they switched to car making during the 1950s. Some, such as Ford and General Motors, offer a wide range of makes so that people can choose a model that fits their lifestyle. Other companies, such as Volvo and Mercedes-Benz, specialize in luxury models.