Automobiles are vehicles for transportation on land, used to carry passengers. They usually have four wheels and an internal combustion engine fueled most often by gasoline (a liquid petroleum product) but sometimes by diesel fuel or even electricity. They are one of the most universal of modern technologies, manufactured by a vast industry and a major component of global commerce. The term automobile is derived from the Greek prefix auto (self) and Latin for motor (car).

The scientific and technical building blocks of the modern automobile can be traced back several hundred years to the Dutch scientist Christiaan Huygens’ invention of the pendulum-type internal combustion engine sparked by gunpowder in the late 1600s. The development of the automobile as a practical means of transport was accelerated in Germany and France toward the end of the 19th century by such inventors as Gottlieb Daimler, Karl Benz, and Nicolaus Otto. In the United States, the automobile became popular among the middle class after 1912.

An automobile provides freedom and mobility that is unmatched by other forms of personal transportation. It has brought about new leisure activities and businesses, including resorts and amusement parks, hotels and motels, restaurants, and fast food chains. It also has prompted changes in government regulations and laws, such as seatbelts and highway rules. Automobiles can also cause harm to the environment, as air pollution from exhaust is a significant contributor to climate change.

Automobiles come in a variety of shapes and sizes, with different amenities and features. There are sports cars, sedans, and station wagons for family use; trucks and commercial vehicles for business use; and luxury cars for the wealthy. In addition, there are off-road vehicles and automobiles designed for particular purposes, such as towing or navigating snow.

Most automobiles have a gasoline-fueled internal combustion engine that powers all the vehicle’s wheels when it is accelerating or cruising. Some have a battery-powered electric motor that takes over while the vehicle is stopped or at lower speeds to save fuel and to reduce emissions. There are also hybrid cars, which have both a gasoline and an electric motor and can run in either mode when necessary.

The automobile is the most widely used mode of passenger transportation in the world, and there are more than 1.4 billion of them in operation worldwide. They are built by many manufacturers, which offer a wide range of styles and prices. In order to compete, each manufacturer seeks to improve the performance of its cars by developing new technical developments and by lowering production costs. To achieve these goals, the manufacturers must develop durable and reliable products that are optimized for their intended uses. For example, automobiles designed for off-road driving must have durable, simple systems that are capable of withstanding severe overloads and harsh operating conditions, while those meant for high-speed, limited-access road systems require increased passenger comfort options, higher engine performance, and optimized high-speed handling and stability. A broad range of research and development engineers are employed in the manufacture of automobiles to ensure that they keep up with these technological advances.