A modern automobile is a highly complex technical system that employs many subsystems with specific design functions. Thousands of individual parts comprise the automobile, and each has its own function. The arrangement, choice and type of these parts depends on the purpose for which the car is designed; an automobile built for speed requires more fuel and a more sophisticated suspension system than an automobile intended for comfort.
The automobile consists of a chassis, on which the engine and wheels are attached; a steering system; a suspension; and a body. The chassis is the main supporting structure, and it must be strong enough to support the weight of the automobile and flexible enough to withstand shocks from turning and road conditions. The steering system consists of a wheel and a steering gear assembly, connected to the front wheels by tie rods. The wheel is connected to the gear assembly by a shaft, and the circular movement of the steering wheel is converted to the linear, or straight, motion of the front wheels. The suspension consists of springs and shock absorbers that provide a cushion between the chassis and the wheel and road surface, absorbing shocks and vibrations. The brakes, which are connected to the wheels by levers and cables, stop the automobile when a pedal is pressed.
Most modern cars use an internal combustion engine fueled most often by gasoline, a liquid petroleum product. The gasoline is ignited by a spark plug to produce combustion, which then powers the wheels of the car. The engine also produces heat, which is carried away by a radiator to keep the motor cool.
An automobile’s appearance is an important part of its design, and the exterior of a car must comply with standards for safety, size and weight, and aerodynamics (the way it affects air flow). The interior of a car must offer comfortable and convenient seating and storage space for passengers. The vehicle must also meet specifications for noise and pollution control.
Modern life would seem almost inconceivable without the automobile. In the early 20th century, people changed from riding horses or trains to driving cars, and entire societies restructured themselves around the power of rapid long-distance travel conferred by these machines. Automobiles allow us to live our lives at our own pace and to take advantage of opportunities that might otherwise pass us by.
Having a car can be especially beneficial when living in the city, where public transportation may be limited. A car can also give families a greater sense of freedom and security. In a time of crisis, having a car within reach allows you to respond to unforeseen circumstances as they arise. For example, if your child becomes sick or injured, having a car provides you with the ability to transport them quickly to a hospital. This gives you a degree of control over the situation that is unattainable with other forms of transportation.