Monday, 9 February 2015
ISO 6346 is an international standard covering the coding, identification and marking of intermodal (shipping) containers used within containerized intermodal freight transport.
The standard establishes a visual identification system for every container that includes a unique serial number (with check digit), the owner, a country code, a size, type and equipment category as well as any operational marks.
The standard is managed by the International Container Bureau (BIC).
Here you can find a very useful page on wikipedia.