Automobiles are vehicles that can be driven and powered by gasoline, diesel, or other fuel. They usually have four wheels, and they are built mainly to transport people.
The first automobiles were horse-drawn carriages fitted with engines. Gottlieb Wilhelm Daimler earned a mechanical engineering degree at Stuttgart Polytechnic and developed the first practical engine, but did not apply it to cars until 1886. He was assisted by Etienne Lenoir, who had also been working on a petrol-powered internal combustion engine at around the same time.
Automobile accidents can cause serious injuries and deaths. Drivers must always be alert and drive carefully to ensure their own safety and the safety of others. Public transportation, such as buses, trains and subways, can take longer to get to destinations but is safer than driving an automobile and may be faster if there are traffic jams or other delays.
An automobile offers a great deal of freedom, convenience and flexibility of use. Entire societies have been restructured around the power of rapid long-distance travel conferred by automobiles and around the flexible distribution of goods made possible by trucks. Automobiles can also cause problems, such as air pollution and traffic congestion.
In the early 20th century, mass production techniques radically changed automotive design. GM, for example, designed models that were similar so that each could compete with the other cars in the market. This meant that the different makes of automobiles often shared parts and components to save costs.