Automobiles are cars, trucks, buses and motorcycles that use internal combustion engines to produce thrust. They are an integral part of our modern world and can be found on roads around the globe. There are an estimated 1.4 billion automobiles in operation worldwide. Most of these are passenger cars. Drivers travel more than three trillion miles (almost five trillion kilometers) each year in them. The automobile has had many benefits for society, but also some drawbacks. One problem is the environmental costs of the vehicles, especially their dependence on oil. Another is the social stigma of driving, which often makes people feel self-conscious and sluggish. The automobile is also a symbol of freedom and personal independence. It can give people freedom from depending on others for transport, and it can help them achieve jobs and places they would not be able to reach in any other way.
Invented in the late 1800s, the modern automobile uses an internal combustion engine that converts fuel into energy to drive the wheels. This engine ignites the fuel by spark plugs and burns it in an air-tight cylinder that is compressed by the piston to push down on the wheels. Some early automobiles were powered by electricity, but they had to be plugged in and recharged.
By 1920, there were more cars in America than there were people in the country. The automobile revolutionized American life, giving people more mobility and access to work and services. New industries and businesses developed to supply the demand for gasoline and automobile parts. Service stations and convenience stores sprang up.
The automobile has shaped culture as well. In the 1910s and 1920s, women embraced the automobile as a symbol of their rights to vote. They drove around with “votes for women” banners, and even gave speeches from their car. Women could also enter professions that were traditionally male-only, such as law enforcement or journalism.
Automobiles are constantly being improved. Research and development engineers and scientists are always trying to improve the body, chassis, drivetrain, engine, and other components of the vehicle. They also look for ways to reduce the vehicle’s consumption of oil and other fuels, while improving safety and efficiency. A good automobile design is cost-efficient to make, has attractive exterior and interior styling, and provides clear visibility for the driver. It should also have a good performance in high speeds and be stable in off-road conditions. It should also be easy to maintain and repair, so that it can be used for a long time. Automobiles that are intended for off-road use need robust systems that can withstand extreme operating conditions. On the other hand, cars that are designed for use on limited-access roads must have better handling and stability at higher speeds and optimized high-speed control systems. This means that they require a different design than vehicles that are designed for use on paved roads. Several factors influence this design, including the distribution of weight between front and rear wheels, the height of the centre of gravity and its relationship to the suspension characteristics of the automobile.