Automobiles are vehicles that are designed to transport people, and usually have four wheels. They are powered by an internal combustion engine that burns fuel to make the vehicle move, which is then transferred to the wheels through a transmission. The most common fuel for automobiles is gasoline (petrol), but some are also powered by diesel, natural gas, or electricity.
The design of an automobile depends on its intended use. Automobiles built for off-road driving need rugged systems with high resistance to overloading and extreme operating conditions. On the other hand, those built for highway speeds must be comfortable and safe for their passengers.
During the early 1900s, American carmaker Henry Ford revolutionized automotive manufacturing by creating the first assembly line, which made automobiles more affordable for middle-class families. The 1901 Mercedes was the first modern automobile, embodying all of the major features of an ideal modern car: comfortable, advanced design; a powerful engine that used little fuel; and moderate price and operating costs.
Today’s cars are complex technical systems with many subsystems that have specific design functions. They include the body, chassis, drivetrain, powertrain, controls, safety systems, and emissions-control systems. To meet market demands, new technologies are constantly being integrated into the vehicles. Examples include computer-aided design and manufacturing, advanced electronic control units, and improved steel and nonferrous metal alloys. Automobiles are an essential part of life, helping us to reach our destinations with greater ease and convenience. They can also provide a sense of security and independence. In an emergency, having a car can help us get to the hospital or home more quickly than walking.