Automobiles are vehicles used to transport people and goods. Most automobiles run on an internal combustion engine, powered by a volatile fuel like gasoline (also known as petrol in some countries). The internal combustion engine converts the chemical energy of the fuel into mechanical energy that drives the wheels of the vehicle. Other sources of power for an automobile are electricity and hydrogen.
The invention of the automobile revolutionized twentieth-century society. It spawned new industries and services, including road construction, hotels, gas stations, restaurants, and amusement parks. It also increased leisure time and made it possible for people to travel long distances for work, vacations, or family visits.
Although the automobile had many advantages, it also caused problems. Exhaust from gasoline-burning cars contributed to air pollution and required new laws to control it. It also forced the loss of large amounts of land for roads, industrial areas, and suburban homes and businesses. In addition, automobile accidents caused injuries and deaths.
Despite these disadvantages, the automobile became the dominant form of transportation in the United States. It was a major source of employment and the economic base for ancillary industries such as steel and petroleum. The demand for automobiles resulted in the development of improved technologies such as high-speed engines, safety systems, and electronic controls.
The modern automobile is a complex technical system with thousands of component parts. The body, chassis, engine, drivetrain, and other parts of the vehicle must work together to make it operate smoothly and safely. Improvements in automotive design have come from research and development efforts by automotive manufacturers, suppliers, and engineers.
There are many different kinds of automobiles, depending on the intended use. For example, off-road vehicles need durable designs that can withstand severe overloads and extreme operating conditions. On the other hand, vehicles designed for highway travel must be quiet and comfortable. Vehicle stability and handling are determined by the location of the engine, its weight, the height of the center of gravity, suspension characteristics, and the selection of front and rear wheels for propulsion.
In the early days of the automobile, there was great competition among manufacturers to produce a reliable car that could compete with horse-drawn carriages on the highways. American carmakers such as Henry Ford pioneered production methods that allowed them to manufacture cars at lower prices than European makers could. This reduced the price of a Model T from over $675 to less than $500, making it affordable for middle-class families. The availability of cheap raw materials and a widespread network of railroads made it possible for automobile manufacturers to sell their products over a wide geographic area. By the 1920s, automobile ownership was widespread in the United States. It seemed that modern life would be inconceivable without it.
