Automobiles are motor vehicles that run primarily on roads and transport people rather than cargo. Most cars today are powered by a petroleum-based internal combustion engine that is either petrol (gasoline) or diesel, with most passenger cars burning gasoline and some of them using the more environmentally friendly diesel. In addition, electric motors are used in some hybrids. The scientific and technical building blocks of the automobile go back several hundred years, and the first self-propelled vehicles were built in Europe in the 1790s and 1800s. The first modern car, developed by French inventor Nicolas Joseph Cugnot, was a three-wheeled steam-powered carriage; it could reach only a few miles per hour and required constant attention to fuel and water.
By the 1920s, as a result of its rapid development, the automobile was one of America’s most important forces for change. It was the biggest customer for steel and petroleum products, and it revolutionized dozens of other industries by providing an abundant market for consumer goods.
American manufacturers sought to meet the demand for affordable automobiles by employing new production techniques such as the assembly line, in which workers stay in one place and perform a single task as parts are moved through the factory. The resulting models were easier to operate and had more amenities than previous automobiles; for example, they offered electric lights, heaters, power steering, and windshield wipers.
As the automobile became more and more central to American life, it became the focus of intense social debates. It brought new forces into play, such as traffic jams and fatal accidents, which prompted calls for licensing and safety regulations. But the automobile had transformed many lives, allowing urban dwellers to rediscover pristine countryside and rural dwellers to shop in town.