Automobiles are a central part of modern society, with impacts on many aspects of life and industry. They are designed by balancing many factors, from performance and cost to passenger comfort and safety. Their evolution began in the late nineteenth century, when Gottlieb Daimler and Karl Benz fitted horse carriages with engines. Throughout the twentieth century, innovations such as automobile manufacturing techniques pioneered by Henry Ford revolutionized industrial production.
Automobiles make it possible for people to travel long distances quickly and easily, allowing them to work in different areas or visit friends and family members who live far away. The rapid, long-distance movement they facilitate has changed society in ways that were not conceivable before the automobile’s invention. Entire industries have developed around the automobile, including those for petroleum, steel, and other industrial products. Automobiles also encourage sprawling, low-density urban development, which degrades landscapes and creates traffic congestion that immobilizes the automobiles themselves.
Most cars run on gasoline, but some use electric power. Those that are powered by electricity have a battery that provides the energy for propulsion when the engine is not running. The engine is usually water-cooled, but some are air-cooled. It may be located in front of the car, in the back, or in the middle and can drive either all four wheels or just two wheels.
The suspension system of an automobile consists of springs and shock absorbers that support the car over rough roads. The suspension helps to keep the vehicle’s weight over the road surface, reducing the strain on tires and other components. It also helps to control the direction of the car and maintain a stable ride, even at high speeds.