According to their mission all containers are freight containers in spite of their type, features and purpose of using. Every container of 20 feet, 40 feet can be called freight. For example, standard dry cargo container of 20 feet or freight refrigerated container of 40 feet, and so on. Freight containers appeared long ago, but they were transformed to containers in the 60s of the last century only. Most likely appearance of freight containers is a natural development of transportation process. Every transport uses containers. The containers are present in almost all freight operations. All containers are labeled according to the purpose of using. Marking of containers and wagons passes directly on the factory where they are produced. Further a freight container moves to the place of storage waiting for its first shipment. The container will be registered and this will mean that it is ready for using.
Containers used in sea and railway and road transportations are the most suitable for large capacity freight operations. It is hard to imagine if each country introduced its own standard for freight containers and the containers running on the territory of one state did not fit the standards adapted to freight containers of the others. It would be a big problem, and there are still railway containers of 20 and 40 feet which cannot be sent by sea. In times of globalization containers for freight using were unified. Foot system came from common unit of measure in the trade; therefore, like most innovations freight containers satisfied the trading class of that time with their length and capacity. For the Russian system of measures 6 meter and 12 meter containers can be corresponded with freight containers of 20 feet and 40 feet accordingly. Although 20 feet are almost 6 meters, but not exactly.
Freight containers for modern vessels and wagons and semi-trailers has changed a little; now there are containers of larger volume, containers that are longer than the standard sizes and wide freight containers called PALLET WIDE. Freight containers are still developing. Producing the first containers it was hard to think that separate containers with refrigeration unit or containers for liquid cargoes will appear. Of course, the standards are also changing but not so much.