Automobiles are motor vehicles designed to carry passengers (or cargo) over a long distance. They usually have four wheels and are powered by an engine which may be gasoline, air, water, liquefied petroleum gas (LPG), natural gas, diesel fuel or electricity. The engine’s power is transferred to the driving wheels through a transmission system, and the chassis of the automobile rests on a suspension system which absorbs shocks from the road surface. Modern cars also contain a range of safety and control systems, including brakes, steering, traction, lighting and air conditioning.
The first car was designed by Karl Benz in Germany around 1885, but the first mass-produced cars were made by Henry Ford in the United States starting in 1910. He used assembly lines to build cars more quickly, and this revolutionized the industry. Today, automobiles are the dominant form of personal transportation, with over 1.4 billion cars in operation worldwide.
There are many advantages to having an automobile: it is faster than walking or riding a bicycle for long distances; can carry more people than a bicycle or bus; and can go places that other wheeled transportation cannot. However, automobiles can pollute the environment with exhaust and other pollutants; cause traffic congestion; and make driving dangerous when not driven properly.
Despite their drawbacks, automobiles have changed the way societies are organized. They allow families to explore remote regions and rediscover pristine landscapes, and they encourage suburbanization of urban areas. They allow people to shop at stores in towns and cities and to visit friends and relatives at a moment’s notice. Teenagers gain independence and confidence by having their own vehicle, and dating couples benefit from having a private space that they can share together without relying on others.
The development of automobiles has been driven by technical developments in the engine, chassis, bodywork, and other components. The most significant innovations are the self-starter, the closed all-steel body and the syncromesh transmission. The design of the engine and its relationship to other automobile systems is affected by its size, weight, power, efficiency, and cost. For example, the choice of whether a car has front-wheel or rear-wheel drive affects its handling and fuel economy. Other choices, such as independent suspension for all four wheels or the use of computer technology, require changes in other systems to work effectively. Finally, there are regulations that govern size and appearance as well as safety and pollution control features.