TEU (Twenty Foot Equivalent Unit) is the unit of the capacity of a container ship, a container terminal and the statistics of the container transit in a port. The two most common international standard containers, are those of twenty and forty foot units. Depending on whether the ship loads twenty or forty-foot containers or a combination of the two, the number of containers held onboard the ship will differ. In order to express the capacity of a container ship in a uniform manner, the number of containers that the ship can load is converted into a number of containers of the smallest size, which are twenty foot in length. A forty-foot container is regarded as two twenty-foot containers or 2 TEU.