These generally require an agreed set of rules, or a central coordinator.
The schemes can be considered to be examples of a primary key of a database management system table, whose table definitions require a database design.
A numbering can be used to transfer the idea of computability[1] and related concepts, which are originally defined on the natural numbers using computable functions, to these different types of objects.
A simple extension is to assign cardinal numbers to physical objects according to the choice of some base of reference and of measurement units for counting or measuring these objects within a given precision.
In such case, numbering is a kind of classification, i.e. assigning a numeric property to each object of the set to subdivide this set into related subsets forming a partition of the initial set, possibly infinite and not enumeratable using a single natural number for each class of the partition.