Intermodal container

An intermodal container, often called a shipping container or ISO Container, is a large standardized container designed and built for intermodal freight transport, meaning these containers can be used across different modes of transport – from ship to rail to truck – without unloading and reloading their cargo. Intermodal containers are primarily used to store and transport materials and products efficiently and securely in the global containerized intermodal freight transport system, but smaller numbers are in regional use as well. These containers are known under a number of names. Based on size alone, up to 95% of intermodal containers comply with ISO standards, and can officially be called ISO containers. Many other names are simply: container, cargo or freight container, shipping, sea or ocean container, container van or sea van, sea can or C can, or MILVAN, SEAVAN, or RO/RO. The also used term CONEX (Box) is technically incorrect carry-over usage of the name of an important predecessor of the international ISO containers, namely the much smaller prior steel CONEX boxes used by the U.S. Army. Intermodal containers exist in many types and a number of standardized sizes, but ninety percent of the global container fleet are so-called "dry freight" or "general purpose" containers – durable closed rectangular boxes, made of rust-retardant Corten steel; almost all wide, and of either standard length, as defined by International Organization for Standardization (ISO) standard 668:2020. The worldwide standard heights are and – the latter are known as High Cube or Hi-Cube (HC or HQ) containers. Depending on the source, these containers may be termed TEUs (twenty-foot equivalent units), reflecting the 20 or 40 feet dimensions. First invented in the early 20th century, modern 40-foot intermodal containers proliferated during the 1960s and 1970s under the containerization innovations of the American shipping company SeaLand.