Automobiles are self-propelled vehicles that move without the assistance of other vehicles or animals to power them. They require an engine which turns the wheels and they in turn move the vehicle forward.
The first usable automobile was invented in the 1780's by Ivan Kulibin. He was from Russia and used many of the necessary components that are still in use on modern cars. From then on automobiles were created and used but were not widely available to the public.
Until Karl Benz came along and invented the gas powered engine most self-propelled vehicles were simply scientific experiments and figuring out that it COULD be done but even with an engine the automobile remained a toy for the wealthy rather than a useful feature of society.
They took so long to manufacture that it was not possible for the average person to acquire one until the car makers could figure out how to make them faster and cheaper.
Oldsmobile was the first company to attempt mass production of cars and they were quite successful at it for awhile. It still wasn't fast enough though.
Henry Ford is considered to be the father of assembly line production. This is the point in time which is most critical to you and I being able to buy and drive a car of our own. Once the time required to manufacture a car fell and they were being mass produced families could then purchase them for their own use.
People were no longer tied to a single piece of land and the expansion of suburbia soon commenced.
Automobiles have many features now that they didn't have then and are highly regulated for safety by the government. An entire industry has evolved to repair and maintain automobiles. There are specialized shops for just tires or oil changes.
The invention of the motorized vehicle is one of the key milestones of modern society. People no longer had to keep draft animals to pull wagons and going 20 miles was no longer a dangerous adventure.
The gas powered engine is considered to have significant impact on the environment and companies are trying to come up with alternatives fuel that can power a car and still remain as economically feasible as what we currently have. At this point alternative fuels are not a cost effective option for most people and we continue to be dependent on the gas powered automobiles that are so familiar to us all.