Automobiles offer the mobility and flexibility of use demanded by an enormous variety of lifestyles and industries. Their development has revolutionized the design of cities, police, fire, and utility services, as well as such personal uses as vacation travel, dining, and shopping. Mass production techniques developed for automobiles in the early twentieth century made them affordable for the mass of American families.
An automobile is a complex machine with thousands of parts. Its individual systems work together much like the human body: the engine–the “heart” of the car–produces power and control; fuel, air, cooling, and lubrication systems keep it running and in good working order; and the chassis–including tires, wheels, and suspension system–provides the necessary stability.
The arrangement, choice, and type of automobile components depends on the vehicle’s intended use. Off-road vehicles require rugged, simple systems that can withstand severe overloads and extreme operating conditions; high-speed cars need passenger comfort options and optimized high-speed handling and stability.
Millions of people worldwide depend on automobiles for transportation to work and school. The industry supports many jobs in factories, at gasoline stations and restaurants, and in motels where travelers stop. But accidents involving automobiles kill millions of people every year, and the use of petroleum products is rapidly depleting world oil reserves. In addition, pollution from automobiles is a serious problem.