An automobile, or motor car, is a wheeled vehicle that uses an internal combustion engine to run. Most definitions of the word specify that automobiles run primarily on roads, have four wheels, and carry people rather than cargo. Since their introduction in the early 1900s, automobiles have transformed society, revolutionized urban life and shaped modern economic growth. They are one of the most significant technological achievements of all time, and an icon of American culture.

The first modern automobile was invented in the late 19th century. It was powered by a gasoline-fueled internal combustion engine. Its inventor is usually credited to be German Karl Benz, who built the Benz Patent-Motorwagen in 1885. The car was an important development because it enabled families to travel farther for work or recreation, and also because it became a symbol of the emerging middle class.

Automobiles have a great impact on the economy and society of their owner countries, especially in developed economies, where they make up the majority of all personal vehicles. They are a large consumer of raw materials and energy, as well as a source of pollution. The United States is the world’s leading automobile manufacturing country, producing more than 70 million units each year. The industry is a major employer and an important contributor to the nation’s economic prosperity.

In general, the design of automobiles depends to a great extent on their intended use. Autos for off-road use, for example, require durable systems with high resistance to severe overloads and extremes of operating conditions. On the other hand, cars designed for fast driving on limited-access highway systems must have optimized passenger comfort options and superior performance in high-speed operations.

Automobile manufacturers produce many different models of vehicles in order to meet the needs of a diverse consumer market. To achieve this, they often share parts, such as hoods, doors, and roofs, with other marques of the same manufacturer. This system of interchangeability was exemplified in a famous demonstration by Henry M. Leland of the Cadillac Motor Car Company in 1908, when three Cadillacs were disassembled, their parts were mixed together, and then the vehicles were reassembled and driven for 800 km (500 miles).

Automobiles are a symbol of the modern era of industrialization and globalization. Their popularity has created a wide range of consumer preferences, as shown by the variety of styles and features available on today’s vehicles. This trend is likely to continue in the future, as manufacturers respond to changes in consumer demand for fuel efficiency and safety equipment. They are also responding to rising concern over environmental concerns, such as air quality and noise level. The resulting range of choice allows consumers to select the automobile that best suits their personal tastes and lifestyles. This is a dynamic and changing field, and the future of the automobile looks promising. Special automobiles include fire engines, ambulances, patrol cars and emergency vehicles. These are usually specialized and modified cars designed to meet specific requirements, for example: