Personal transportation is dominated by the automobile, which work on the network of 13 million road,As well as one of the world's longest highway system The automobile market is the world's second-largest The United States has the highest rate of car ownership of per capita of the world, with up to 765 cars, to 1000 Americans about 40% of personal vehicles, light truck or van offroad The average American adults (count all the people and those who don't drive) takes 55 minutes drive every day, travel 29 miles.