Automobiles are motor vehicles used for passenger transportation. Modern automobiles have four wheels, and their internal combustion engines are powered by gasoline (a liquid petroleum product), which is the most common fuel in use today. The modern automobile has become one of the most important of human technologies and an integral part of urban life, with some 1.4 billion cars in operation worldwide.
Invented in the late 1800s, the automobile has had a dramatic effect on society. It has greatly expanded the freedom of movement in many countries, making it possible for people to live in distant cities and work in far-away offices or factories. It has also allowed families to spend more time together.
The modern automobile is a complex system that has evolved over more than a century of development. It is often designed to meet strict safety standards, and it must comply with laws regarding size, weight, aerodynamics, engine efficiency and emissions control. It must be able to handle the stresses of driving over rough roads, as well as highway speeds and cornering.
The automobile industry has developed a number of important innovations that have revolutionized human transportation. Using mass production techniques, automakers have been able to produce a wide variety of models at very affordable prices. In addition, automobiles are equipped with a host of other technological and mechanical devices. They are also a vital component of the modern economy, providing a means of transportation for heavy equipment and materials.