In the [[United States]], most products are shipped via professional trucking. In prior times, the [[railroad]] shipped a lot of goods, but the development of the [[National Highway System]] and the consequent general shift from rail transit to the [[automobile]] is put more emphasis on trucks as opposed to rail. Very little [[freight]] is transported by [[air]]; [[air mail]] being one key exception. (In contrast to the public [[USPS]], [[privatized]] mail services such as [[DHL]] and [[Federal Express]] still deliver mail in trucks.) Each day, more than 1 million tractor trailers and semis hit the road. | In the [[United States]], most products are shipped via professional trucking. In prior times, the [[railroad]] shipped a lot of goods, but the development of the [[National Highway System]] and the consequent general shift from rail transit to the [[automobile]] is put more emphasis on trucks as opposed to rail. Very little [[freight]] is transported by [[air]]; [[air mail]] being one key exception. (In contrast to the public [[USPS]], [[privatized]] mail services such as [[DHL]] and [[Federal Express]] still deliver mail in trucks.) Each day, more than 1 million tractor trailers and semis hit the road. |