The advent of the automobile revolution was largely the result of economic development. In the United States, a relatively higher per capita income and more equitable income distribution led to a demand for automobiles. In addition, the American manufacturing tradition lowered prices and made the automobile affordable to middle-class families. Increasing numbers of people are now using automobiles, and in the United States alone, 4.8 trillion km (3 trillion miles) are driven each year.
Despite common belief, not all vehicles are automobiles. Motorcycles are not classified as automobiles because they are not car-like or have a sidecar. The legal definition of an automobile is a vehicle with four wheels and the ability to carry many passengers. In addition, a motorcycle is not considered an automobile if it is three-wheeled or has a sidecar.
Automobiles started as bicycle-like contraptions. During the mid-Victorian era, a bicycle builder named Ernest Michaux created a similar contraption. Another bicycle builder named Sylvester Howard Roper created a similar machine in 1867. In 1885, the internal combustion engine was invented.
Automobiles are the most common form of transport in our society. They are designed to carry passengers and goods. Today, automobiles are highly complex technical systems with thousands of component parts. They play an important role in modern society and serve as a lifeline for humans.