Automobiles are a type of transportation vehicle that can be propelled by an internal combustion engine using a volatile fuel. They are generally four-wheeled vehicles designed primarily for passenger transport and often used in combination with other types of vehicles to form a multipurpose vehicle.

There are many different kinds of automobiles, each with its own design features and functions. They vary widely in size, shape, weight, performance, and safety. They are usually referred to by their brand name or by the model number.

The design of an automobile depends largely on its intended use, although other factors such as requirements for pollution-control components and standards of safety affect the car’s design. The most important subsystems in an automobile include the engine, transmission, and chassis.

An automobile can have from four to eight cylinders and has at least three forward gears, usually with a reverse gear. The size of the car and the amount of power required will determine how many cylinders it needs.

In the early days of the automobile, most manufacturers assembled existing parts to produce finished cars. They did not need a lot of capital to enter this business. During the first half of the twentieth century, Ford production methods, perfected in the Highland Park plant, Michigan, and used in the manufacture of other products, led to a steady decline in the price of cars, allowing them to be made within reach of more American consumers.

As the automobile industry grew, it also facilitated the growth of other industries that had long been dominated by horse-drawn wagons and stagecoaches. These industries shifted to new lines of manufacturing, and the shift created opportunities for remunerative industrial employment for many unskilled workers.

The automobile’s ability to quickly and efficiently move large numbers of people had an immense social impact. It transformed cities, reorganized work and leisure patterns, sparked urban redevelopment, and spawned a burgeoning consumer culture. It also fueled the development of a large and remunerative middle class that, in turn, influenced the shaping of public policy and the economy.

But the automobile also brought problems, as it encouraged sprawl (i.e., straggling, low-density urban development) that degrades landscapes and produces traffic congestion. In addition, it had a negative effect on the personal freedom of its users and eroded traditional family values, such as courtship and authority. And it made cities prone to traffic jams and parking problems, which strained municipal budgets and undercut the tax base.