Few inventions have had as large an impact on everyday life as the automobile. Since its development in the late nineteenth century, the car has become the primary mode of transportation for most people in the world. In fact, modern life would be inconceivable without it.
The automobile consists of many systems: the chassis and body, steering system, electrical system, cooling and lubrication system, internal combustion engine, wheels and tires, suspension system, and braking system. Each of these systems is designed to interact with the other, allowing for smooth and safe operation of the vehicle.
Most contemporary automobiles are powered by a piston-type internal-combustion engine fueled by gasoline. The engine drives either the front wheels or, in more advanced models, all four wheels. The power may be transferred to the wheels via a transmission system, or, more commonly, by differentials. The braking system is often assisted by friction brakes, in which the motion of one stationary surface rubs against another moving surface and slows it, or by mechanical brakes that use friction to hold the car at rest.
Many other systems have contributed to the advancement of automobiles, such as electric ignition (developed by Charles Kettering for General Motors in 1910) and independent suspension, which allows each wheel to react independently to variations in the road surface. A number of pistonless rotary engines, such as the Mazda Wankel design, have been developed but have not yet had significant commercial success.
The design of the automobile must incorporate a wide variety of factors, including safety features, size and weight, the cost of the vehicle to consumers, and even aerodynamics or ways to reduce the drag caused by air flow over the body. Consequently, automobile designs are constantly changing to reflect new technical developments.
One factor influencing this process is the demand for a certain type of automobile. For example, the United States has a much larger geographic area than Europe, so it makes sense that there should be great demand for cars to drive across this huge land mass. Furthermore, American manufacturers are encouraged by a tradition of mass production and the availability of cheap raw materials.
As a result, many different types of cars are manufactured. To meet the varying needs of consumers, companies such as Ford have developed an assembly line process that allows them to produce large numbers of the same basic model at a very affordable price. In addition, most companies offer a variety of options or upgrades to the base model in order to attract buyers. The result is a tremendous number of automobiles with a variety of technical and cosmetic characteristics. However, all modern automobiles are constructed with some of the same fundamental components.
