Automobiles are four-wheeled vehicles that use a combustion engine to propel themselves forward. They are one of the most influential inventions in modern history, changing industrial and technological progress, everyday life and culture. It gave people more personal freedom and access to jobs and services. Industries and new jobs developed to supply the demand for automobile parts and fuel. These included petroleum and gasoline, rubber and then plastics. Services like gas stations and convenience stores also sprang up.
The first cars were steam and electrically powered, but the gasoline-powered car eventually won out. By 1920 it had overtaken streets and highways throughout the world. The innovations of Henry Ford and other mass producers reduced costs so that cars were within the reach of middle-class Americans. The automobile became a major force in the new consumer goods-oriented society of the 1920s, providing one out of six jobs.
It also introduced new lifestyles and challenges. The freedom it offered encouraged family vacations to places that were previously out of the reach of most. Urban dwellers could rediscover pristine landscapes and rural residents could shop in town. Teenagers gained independence with driving freedom, and dating couples discovered a portable place for relaxed sexual attitudes. Traffic jams, fatalities and other hazards soon prompted demands for licensure and safety regulation on the state level.
Modern automobiles are available in a wide range of styles and prices from dozens of manufacturers from Acura to Volvo. While there are only 10 basic body types, they are available in a wide range of sizes and in various configurations. For example, some models, such as the Subaru Outback and Audi A4 Allroad, have elevated ground clearance and rugged body cladding to make them more SUV-like.