In the United States there are five main types of trucking, or motor freight transportation: private carriers, local cartage carriers, over-the-road common carriers, over-the-road contract carriers, and piggyback carriers. Many other countries have similar types.
A private carrier is one who hauls his own goods in his own vehicle. A dry-cleaning establishment, for example, may have its own truck for pickup and delivery service to its customers. Many larger companies have fleets of trucks to deliver their goods. A local cartage carrier operates within a city and suburban area and carries goods for others. The United Parcel Service, for instance, operates essentially as a local cartage company, though it is known as a national corporation.
An over-the-road common carrier operates between cities and often between states, and it carries all types of freight for different customers. The over-the-road contract carrier also operates between cities and states, but it has contracts with one or more customers to carry specific kinds of freight.
Piggyback service emerged in the 1960s and represents cooperation between railroads, ship lines, and the trucking industry. A piggyback train consists of specially built flatcars that carry fully loaded truck trailers. The trailers are hauled to the train yards by the truck tractor and lifted onto the flatcars by large cranelike machines. When the trains arrive at their destination, the trailers are lifted off and attached to other tractors, which haul them away. Similarly, the trailers may be brought to harbors to be loaded onto ships for delivery overseas.
Very similar to the piggyback trailers was the development, also in the 1960s, of containerization. Containers are similar to trailers, but they have no wheels. It is therefore possible to stack one on top of another on large oceangoing freighters. They can also be hauled on the highway on specially designed truck chassis. The advantage of piggyback and container transport is in the saving of loading and unloading time and in the large amount of goods that can be hauled at one time, using fuel for only one engine.
The United States has the world's largest trucking industry, with more than 36 million trucks of all types in service. Japan is second, with more than 17 million trucks. In Europe, France has the largest trucking system, with more than 3 million vehicles; the United Kingdom is second, with more than 2 million.
Freight can be transported by ship, river barge, train, airplane, and truck. The advantage that most other forms of transport have over trucks is the amount that can be carried at one time. But trucks have the advantage of accessibility. They need only roads or highways on which to travel, while other forms of transport are limited.
Ships, for example, can enter harbors, but they can deliver goods no farther; trains must remain on tracks and barges in rivers. Hence, the economies of industrialized nations depend quite heavily on truck transport to get goods where and when they are needed.
