Automobiles are wheeled motor vehicles that run on roads and seat one to eight passengers. They are generally propelled by internal combustion engines (using volatile inflammable fuels such as gasoline, petrol, naphtha, alcohol, or diesel) although they may be powered by steam engines, electric motors, or other sources of energy. Various models have been designed with different body styles, braking systems, suspensions, and propulsion systems. The term automobile is derived from French auto- (self) + mobile (carrying).
Cars are the most advanced and versatile of modern transport systems. Their design depends on a number of factors, the most important being their intended use. Automobiles that are primarily for local use require simpler systems with high resistance to severe overloads and extreme operating conditions; those designed for high speed, limited-access road use demand more passenger comfort options, increased engine performance, optimized steering and handling capabilities, and improved safety features.
The first automobiles were introduced in the United States in the early twentieth century. At the time, the American middle class was growing and more people could afford to own cars. The introduction of the automobile changed American society in many ways. Cars gave people more freedom and allowed them to do more things in their spare time. People living in urban areas were able to escape to the countryside, and those who lived in rural areas could visit cities.
Cars are also an essential mode of transportation for families. They allow parents to drive their children safely to school or activities, and they can take their children on outings together. They can also be used for business trips or for a late-night ice cream run.