Automobiles are cars, buses, trucks, motorcycles and other vehicles that can be driven on public roads. They are powered by internal combustion engines using a volatile fuel and have several systems to power, control and support them and to make them comfortable for passengers. The modern automobile is a complex machine that consists of thousands of parts. Some of these parts are designed to protect the vehicle from collisions with other objects, to keep it running smoothly, and to provide safety features such as airbags. The automobile has many benefits, including its ability to take people where they want to go, at a time that suits their schedule. But it can also cause problems such as traffic congestion and the pollution of the air that people breathe.
The first practical automobiles became available for use around the turn of the twentieth century. They replaced horse-drawn carriages and were made in factories that used the new mass production techniques pioneered by Henry Ford. Cars were originally powered by steam, electric power or gasoline. Steam cars could travel quickly but burned a lot of fuel and had a short range. Battery-powered electric cars were more convenient to start but required frequent recharging and did not travel far on a charge. Gasoline-powered automobiles were able to reach high speeds and go farther on a charge than steam or electric cars, and they did not need regular refueling.
In the United States, cheap raw materials and a tradition of manufacturing encouraged the development of the automobile. Its vast land area and the absence of tariff barriers encouraged sales over a large geographic region, and it also had a rich supply of natural resources and an abundant population of skilled laborers. Its consumer demand for automobiles was helped by the availability of credit and a more equitable distribution of incomes.
After the World War II, the automobile spread to countries throughout the world. Its availability and affordability allowed more and more people to move from rural areas into cities and work for industrial companies. This boosted the economy and created new opportunities for jobs and housing. People can also travel long distances more easily with an automobile, opening up their options for where they live and work.
Almost everyone knows what an automobile is. They are the four-wheeled passenger vehicles that most of us drive on a daily basis. They can be driven by one person or they can hold more people and luggage. They are faster than walking or riding a bicycle and can reach places that are not accessible to buses, trains (steam-powered, diesel-powered or passenger), or trams. There are special automobiles for various purposes, such as crane vehicles at construction sites and warehouses and emergency vehicles (fire, ambulance, patrol cars and so on). They can run on gasoline, diesel fuel or electricity. Many of them are made in the USA, Japan, France and Germany. The automobile has become the most common mode of transportation in the world.