Automobiles are wheeled vehicles that move under their own power, without relying on horses or any other external motivating force. The word “automobile” comes from the Greek prefix “auto” (“self”) and the Latin verb “mobilis” (“to move”).
Modern automobiles have evolved into sophisticated systems, shaped by factors such as safety requirements, fuel economy, appearance, and emissions control. They are designed to work well in a wide range of operating conditions, varying from the rugged environments of off-road vehicles to high-speed roads where aerodynamics and handling play an important role.
The basic elements of an automobile are a body, chassis, and engine. The engine uses an internal combustion of gasoline, diesel, or kerosene to produce a force that turns the wheels of the car. This force is used to carry the load of people or cargo and to propel the vehicle. The automobile’s brakes use friction to stop the vehicle, and regenerative braking turns some of the energy from the motion of the car back into electricity to recharge the battery.
An automobile’s materials are chosen to balance several competing factors. For example, the safety of passengers and their luggage require strong, durable materials that withstand a variety of loading conditions. At the same time, the automobile must be light enough to make it economically viable, and it must comply with government regulations on fuel efficiency and safety features. The modern automobile is a complex system that has evolved over the past century, and its future direction is uncertain.