What Are Automobiles?

Automobiles (also called cars) are motor vehicles that primarily run on roads and seat one to eight people. They are usually powered by gasoline, although they may also be powered by other fuels such as natural gas or electricity. The first automobiles were steam-powered, but the internal combustion engine soon replaced them. The automobile revolutionized transportation, spurring the development of new industries and creating jobs that made modern life possible.

The automotive industry has a rich history of innovation and technical breakthroughs. Among the most important was the invention of the assembly line by Henry Ford, which enabled automobiles to be produced at scale and affordably for many middle-class families. Other major advances include the introduction of safety features, such as airbags and seatbelts; electronic systems like GPS and satellite radio; and advanced materials such as lightweight aluminum and high-strength steel. In addition to improving vehicle performance and quality, these developments have reduced vehicle emissions and lowered operating costs.

Most automobiles use a gasoline-powered internal combustion engine to turn the wheels of the car. The energy of the engine is turned into mechanical energy by a transmission or drivetrain, which sends it to the wheels. The amount of power available is measured in kilowatts or horsepower. Some automobiles use an electric motor to drive the wheels, but most use a conventional friction brake system that turns the wheel axles to slow or stop the car. Some electric automobiles have regenerative brakes that convert the energy of the car’s movement back into electricity.

Compared to walking or riding a bicycle, automobiles can carry more people and luggage and get to places faster. They can also go places that are inaccessible to other types of wheeled transport, such as mountainous or off-road terrain. However, automobiles use a lot of fuel and generate pollution, which can be an issue if too many are used in a small area, as is the case in cities and some rural areas.

Buying an automobile is a big financial commitment, so it’s important to do your research and select the model that’s right for you. The best automobiles offer a combination of comfort, capability and value, along with a long warranty. Those with the longest warranties generally have the highest reliability records. The least reliable cars typically have the lowest fuel economy and performance, as well as the most expensive repair bills. Consumer Reports’ annual rankings can help you identify the best automobiles to buy and avoid, based on road tests and long-term ownership costs. The top brands consistently earn high marks in our ratings, but some of them experience significant year-to-year shifts in their ranking. These shifts often reflect improvements or disappointments in model-year reliability. For example, Genesis made the biggest leap this year, rising 12 spots on the strength of its excellent reliability record. Chrysler dropped a dozen spots, dragged down by the below-average reliability of the Pacifica Hybrid minivan.