Automobiles are motor vehicles used for transporting people. They run primarily on roads, have four wheels and usually seat one to eight passengers. Most definitions of automobiles include cars, truckes, vans, minivans and sport utility vehicles (SUVs). Automobiles are a vital part of the modern world, and they can be used for recreation, business or daily transportation. Owning an automobile provides the freedom to travel at will and visit places that would otherwise be inaccessible or difficult to reach without one. While many people today are getting out from behind the wheel and walking, taking public transit if possible or carpooling to work instead of driving themselves, the convenience and benefits of owning a vehicle remain considerable.

The first automobile was invented by Karl Benz in 1885, and his design was soon copied by other inventors and engineers. The earliest automobiles were expensive and limited in number, but the advent of Henry Ford’s mass-production techniques revolutionized the industry. He introduced the Model T, a more affordable vehicle that enabled middle-class families to own a car. As the automobile became more commonplace, it altered American society in fundamental ways. It was virtually impossible to imagine a modern life without a vehicle by the 20th century.

Automobile designers are influenced by a number of factors, including the intended use of the vehicle and safety concerns. For example, vehicles that are designed to drive on rugged off-road terrain must be durable and have simple systems to resist severe overloads and operating conditions. In contrast, those that are designed for high-speed highway use require passenger comfort options, optimized engine performance and handling capabilities, and enhanced braking and steering functions.

Other considerations are the type of fuel that is used, as well as the vehicle’s overall weight. Some manufacturers use lightweight materials such as aluminum, titanium and carbon fiber for the body, chassis, suspension and other components to reduce the vehicle’s weight, while retaining strength. This allows the manufacturer to achieve a better power-to-weight ratio, which improves vehicle performance.

The automotive industry is characterized by high competition and a steady flow of innovations, with new models appearing nearly every year. Hundreds of small manufacturers have come and gone, but the big three — Ford, General Motors and Chrysler — have dominated production since the 1920s.

Most modern automobiles feature a number of standard features such as electric ignition and self-starting, a closed all-steel body, hydraulic brakes, a syncromesh transmission and four-wheel drive. In addition, a variety of advanced systems have been developed to enhance automobile performance and safety, such as antilock braking, electronic stability control, and airbags.

There are also special automobiles that are designed to perform tasks such as construction, cargo transport and emergency rescue. These vehicles include the crane vehicle in a construction site, a fire engine at a fire scene and a forklift in a warehouse. In the United States, there are even automobiles built for military purposes such as armored vehicles and combat cars.