Tumblers are multi-part ordinal numbers similar to the Dewey Decimal System. For example, 188.8.131.52 and 184.108.40.206.1.3.4 are both tumblers. Since they can expand at any point, a numbering system based on them never runs out of precision. Udanax Green uses tumblers for all address to allow any number of nodes, users, documents, data-bytes, and links. (See the chapters "Addressing" and "Tumbler Arithmetic".) A document initially created as a virtual copy of some other document.