The automobile is a road vehicle that first appeared in the nineteenth century. The first cars were propelled by steam, but were not a success. The age of the motor car really dates from the introduction (1885–82) of the gasoline-driven carriages of Gottlieb Daimler and Karl Benz. The internal combustion engine of these cars had been developed earlier by several engineers (most notably Nikolaus Otto in 1876).
The main components of a motor car remain unchanged. A body (chassis) to which are attached all other parts including: an engine or power plant; a transmission system for transferring the drive to the wheels, and steering, braking, and suspension for guiding, stopping, and supporting the car.
Early cars were assembled by a few experts, but modern mass-production began in the early 1900s by Henry Ford and R. E. Olds in the United States. In most modern car factories, component parts are put together on assembly lines. Each worker has a specific task (such as fitting doors or crankshafts). Bodies and engines are made on separate assembly lines which converge when the engine is installed. Overhead rail conveyors move heavy components along the assembly lines, lowering them into position. The final stages of assembly including the fitting of items such as lights and paint spraying. Electrical, braking, and control systems are checked. The assembled car is tested before sale. Recent technology has seen the introduction of robots (specifically, robot arms secured to the workshop floor) on the assembly line. They are usually used for welding and painting.
Increasing concern over the environmental impact of the car (such as congestion, pollution, and energy consumption) has encouraged governments to examine alternative forms of mass transport, oil companies to produce cleaner fuels, and car manufacturers to look at alternative power plants, such as electric- or gas-powered motors.