A module describing the physical storage structures of data files and the relationship of their internal objects to the logical (intellectual) description of the objects found in LogicalProduct. This describes the physical aspects of data files which may be common between one or more data files as described by physical structure of the file and the structure of data items within a record. The PhysicalDataProduct contains the critical links between the physical data store identified by a PhysicalInstance and the logical (intellectual) description of the data as found in the LogicalProduct.