Containerization is a system of intermodal cargo transport using standard ISO containers that can be loaded on container ships, railroad cars, and trucks. There are three common standard lengths, 20 ft (6.1 m), 40 ft (12.2 m) and 45 ft (13.7 m). Container capacity (of ships, ports, etc) is measured in twenty-foot equivalent units (TEU, or sometimes teu). A twenty-foot equivalent unit is a measure of containerized cargo equal to one standard 20 ft (length) × 8 ft (width) × 8.5 ft (height) container (approximately 39 m³). Most containers today are of the 40-ft variety and thus are 2 TEU. 45 ft containers are also designated 2 TEU. Two TEU are referred to as one FEU or "Forty-foot equivalent unit". These two terms of measurement are used interchangeably. "High cube" containers have a height of 9.5 ft (2.9 m), while half-height containers, used for heavy loads, have a height of 4.25 ft (1.3 m).

History

Containerization is an important element of the logistics revolution that changed freight handling in the 20th century. Malcolm McLean claimed to have invented the shipping container in the 1930s in New Jersey, but only founded Sea-Land corporation in the 1950s.

McLean explained that while sitting at a dock waiting for cargo he trucked in to be reloaded onto a ship, he realized that rather than loading and unloading the truck, the truck itself (with some minor modifications) could be the container that is transported.

Containerization revolutionized cargo shipping. Today, approximately 90% of cargo moves by containers stacked on transport ships. Over 200 million containers are shipped per year.

The widespread use of ISO standard containers influenced modifications in other freight moving standards, gradually forcing removable truck bodies or swap bodies into the same sizes and shapes (though without the strength needed to be stacked), and changing completely the worldwide use of freight pallets which fit into ISO containers or into commercial vehicles.