Automobiles are one of the most common forms of transportation in the world. They are usually four-wheeled vehicles, powered by gasoline or diesel engines, which are designed to carry passengers and cargo.

Today, a modern automobile is a complex technical system containing thousands of component parts, including an internal combustion engine. Modern vehicles are capable of driving at highway speeds and are fueled by gasoline or diesel. The body of the car and its components are enhanced by scientists and engineers working for auto manufacturers.

Early automobiles used steam engines. These were less efficient than the internal combustion engines used today. Steam engines had limited range, and starting them was inconvenient.

After World War II, automobile production soared in Europe and Japan. Henry Ford, the founder of the Ford Motor Company, patented a manufacturing technique that made automobiles affordable for middle-class families.

After the advent of the Model T, the first mass-produced car, automobiles became widely popular in the United States. By the 1920s, the gas-powered car had become the dominant form of transportation.

Today, automobiles are generally designed to accommodate two to six passengers. Most passenger cars use gasoline as fuel, although diesel engines are also commonly used.

The automobile industry is considered to be one of the largest in the world. It is estimated that there are about 70 million new passenger cars built each year.

In the United States, for instance, the average citizen drives about three trillion miles per year. This amount of traffic can cause significant pollution. Approximately 34% of hydrocarbon and nitrogen oxide pollution comes from the automobile industry.