Containerization is a system of intermodal freight transport using intermodal containers. Containerization, also referred as container stuffing or container loading, is the process of unitization of cargoes in exports. Containerization is the predominant form of unitization of export cargoes, as opposed to other systems such as the barge system or palletization. The containers have standardized dimensions. They can be loaded and unloaded, stacked, transported efficiently over long distances, and transferred from one mode of transport to another—container ships, rail transport flatcars, and semi-trailer trucks—without being opened. The handling system is mechanized so that all handling is done with cranes and special forklift trucks. All containers are numbered and tracked using computerized systems.

The Bureau International des Containers et du Transport Intermodal oversees standards for intermodal containers, commonly referred to as "shipping containers".