A MIRIAM entry describes a MIRIAM data type including the official name, synonyms, root URI, identifier pattern (regular expression applied to a unique identifier of the data type) and documentation. Each data type can be associated with several resources. Each resource is a physical location of a service (typically a database) providing information on the elements of a data type. Several resources may exist for each data type, provided the same (mirrors) or different information. MIRIAM provides a stable and persistent reference to its data types.