An automobile, or car, is a motor vehicle that moves people around. It usually has four wheels and is powered by a petrol (gasoline) engine, although some have electric or water run engines as well.

Its main purpose is transportation, but automobiles can also be used to carry goods and passengers. Currently, more than 1.4 billion cars are on the roads worldwide, with most being passenger cars. It is the main mode of transportation for the majority of the world’s population and it is responsible for a significant share of global air pollution and energy consumption.

Most modern cars use internal combustion engines to power their wheels and drivetrain, but the first automobiles were powered by a variety of other sources, including electricity and steam. In recent decades, technological advances have allowed for better fuel efficiency and more environmentally friendly systems, as well as a resurgence of interest in alternatively powered vehicles.

During the 20th century, the automobile became a key force behind changes in American society and culture. It spawned the automobile industry, which now ranks as one of the largest industries in the world and provides jobs for millions of people. It has become a major consumer of oil and other petroleum products, as well as a leading purchaser of steel and many other industrial materials. It has helped to revolutionize the way families live and work, giving people more freedom in their leisure activities and allowing them to travel farther for vacations and business.

Since the 1920s, automobile design has been driven by marketing plans and by consumer demand for more comfort and features. In the 1990s, SUVs and minivans grew in popularity as people sought vehicles with more cargo space and seating capacity. More recently, fuel prices have boosted demand for hybrid cars, which combine an internal combustion engine with an electric motor to offer greater efficiency while reducing emissions.

An automobile is a complex machine with thousands of moving parts. The basic components are the frame, body, and engine. The body is the visible part of the car, while the engine is located under the hood or trunk and hidden from view. The engine drives the wheels through a transmission and the gears are connected to the steering wheel and pedals via shafts.

In some countries, it is illegal to operate an automobile without a valid driver’s license and insurance. Some states have additional regulations that apply to specific types of vehicles, such as motorcycles or bicycles. Other nations have more restrictive licensing requirements, such as age restrictions or driving tests for new drivers. Generally, the most important consideration is safety, which can be enhanced by using seatbelts and child safety seats, by obeying traffic laws, and by maintaining a safe speed limit. It is also important to maintain your automobile properly to keep it running safely. This includes regular maintenance, inspections, and replacement of parts. These steps will help your automobile last longer and run more efficiently.