BEC口语素材：Delivery and Shipment 交货和装运

Shipping is a basic process of transporting goods and cargo. Virtually every product ever made, bought, or sold has been affected by shipping. Despite the many variables in shipped products and locations, there are only three basic types of shipments: land, air, and sea. 

Land or “ground” shipping can be either by train or by truck. Trucking is easily the most popular form of shipping. Even in air and Sea shipments, ground transportation is still required to take the product from its origin to the airport or seaport and then to its destination. Ground transportation is typically more affordable than air shipments, but more expensive than shipping by sea. Trucks are also much faster than ships and rail but slower than planes. 

Many trucks will take freight directly from the shipper to its destination in what is known as a door to door shipment. Vans and trucks of all sizes make deliveries to sea ports and air ports where freight is moved in bulk also. 

Much shipping is done aboard actual ships. The ships are also extremely expensive constructions themselves, being some of the largest man-made vehicles ever.   

Air transport is usually reserved for products which must be sent within a shorter time frame. Some carriers offer ground shipping that operates on an exact timeline as air does. This is a recent development becoming mainstream among major carriers since the late 1990s.