Automobiles are vehicles that use an engine to move. They have four wheels and are designed to carry a driver and a small number of passengers. They are more expensive than bicycles or motorcycles but cheaper than trucks, lorries and buses. They are also more convenient than riding in a train or airplane because they allow people to travel at their own pace and stop whenever they want to.

Modern automobiles are usually powered by internal combustion engines. These engines burn fuel such as gasoline, diesel or kerosene to produce power that turns the wheels and supplies electricity for lights.

Cars are complex machines with many different systems that work together. The engine, transmission, steering system and brakes are all essential parts of the automobile. The body is the outer shell that protects the mechanical parts of the car. The driver operates the automobile by pressing on pedals to make it go and stop and turning a wheel to steer it.

The invention of the automobile revolutionized society. It gave people access to jobs, houses and leisure activities that they did not have before. It brought new services such as restaurants, motels and fast food. However, it also brought harm to the environment by causing pollution. Exhaust from the cars was a significant source of air pollution. It also caused the depletion of natural resources such as oil.

Before the invention of the automobile, people got around by walking, riding a horse or using trains and ships. The first cars were steam or electric powered. These were slow and heavy and did not have all the features of today’s automobiles. The most important change was that the automobile allowed ordinary people to own and drive cars. This occurred mainly because of the invention of mass production by Henry Ford. This meant that the cost of producing cars fell and so they could be sold to more people.

In addition to allowing more people to own cars, the automobile made traveling much faster and easier than before. It is often possible to get to places that are too far to walk or ride a bike and can carry more luggage than a bicycle. Automobiles can also go on roads that are too rough or steep for other vehicles.

There are special automobiles designed for particular uses. These include automobiles that carry cargo (lorries, vans), emergency automobiles such as fire engines or ambulances and automobiles that police officers drive. There are also special cars that are used by construction workers, cranes and fork-lifts. All of these types of automobiles need very durable and simple systems because they are exposed to severe overloads and extreme operating conditions. Other special cars are made for off-road use, such as SUVs. These require high-speed capabilities, optimized high-speed handling and a robust chassis design. They must be able to cope with rugged terrain and extremes of temperature. They must also have good cargo capacity and passenger comfort options.