Automobiles are self-propelled motor vehicles that run on roads. They are generally characterized by the use of an internal combustion engine that is fueled most commonly by gasoline (a liquid petroleum product).

The term automobile is also used to refer to other types of motor vehicles such as motorcycles and mopeds. However, the term automobile has become increasingly applied to all wheeled vehicles that drive on the road and are primarily designed for the transport of people.

Some automobiles are designed for off-road use; these are often referred to as trucks or buses. They may be constructed for specific purposes such as to move heavy loads and are therefore subject to a variety of design requirements.

They are built to withstand rough terrain and the impact of large amounts of weight on each axle; they can be designed for low-speed, limited-access road systems or high-speed, long-distance transport. Some are designed for use on mountain roads, and they can be specially engineered to handle the steep climbs and descents that are common on these types of routes.

Other types of automobiles are designed for use on the street and are more suited to driving in dense traffic. They are usually able to run on gasoline, diesel or liquefied petroleum gas and can be powered by an engine or a generator.

Automotive technology has evolved rapidly, due to the hundreds of small manufacturers competing to gain world attention. Some key developments include electric ignition and the electric self-starter (both by Charles Kettering, for the Cadillac Motor Company in 1910-1911), independent suspension, and four-wheel brakes.

The development of the modern automobile was accelerated by the introduction of the internal-combustion engine in 1885 by Karl Benz, a German engineer. Benz was granted a patent for his invention on 29 January 1886, and in 1888 he built the first motor vehicle to be driven commercially.

During this time a number of other engineers in Germany were working on the automobile as well. Gottlieb Daimler and Wilhelm Maybach were among them, and they built several cars from 1885 to 1900.

They were followed by Henry Ford, who introduced the idea of using an assembly line to produce affordable cars. This production line concept made the automobile more accessible to the general public.

There are many different ways that an automobile can be designed, but the most important considerations are stability and comfort for the driver and passengers. Stability can be improved by using a transmission that is capable of distributing torque to all wheels, and by using the most efficient drive train possible.

The car is the most common form of vehicle in the world, and it is used for transportation of people, goods, and passengers on a single journey. It is an essential part of the developed economy and a critical part of life in most developed countries.

Cars are useful for a number of reasons, including the ability to travel at your own speed and to explore new places that might not be otherwise accessible by public transportation. They are also a great way to travel on weekends or for special occasions, and are an invaluable source of personal freedom.