AN AUTOMOBILE (also called car or motorcar) is a four-wheeled vehicle for transporting passengers, usually powered by an internal-combustion engine using a volatile fuel. Benzene, gasoline, diesel fuel and propane gas are all common fuels for automobiles. Automobiles are made up of thousands of individual parts arranged into several semi-independent systems, each designed to perform specific functions. The system that converts chemical energy from the fuel into mechanical energy to drive the wheels is called an engine, or motor, and is measured in horsepower (kilowatts). Another system, analogous to the human circulatory system, delivers coolant and lubricating oil to the engine. A chassis, or body, provides support for these systems and protects the occupants from weather, noise and vibration.
The automobile has a long history of changing lifestyles, from providing the means for people to live and work in remote areas, to making it possible for families to spend vacation time together. Modern automobiles also make it possible to get medical care, groceries, food, clothing and other products quickly and efficiently. Mass production techniques developed for automobiles in the early twentieth century allow them to be produced at very low cost, allowing ordinary people to afford them.
Owning a car gives you freedom to travel at your own pace without the need to worry about missing the bus or other forms of public transportation. If you have a hectic schedule, being able to cross town in a matter of minutes saves time for day-to-day trips, shopping trips and visits to friends and family.