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FOLIO instances are equivalent to bibliographic records in function but not in format. The native FOLIO format is flexible and can accommodate data from multiple formats including, but not limited to, MARC. Because of this, mapping needs to be defined. Some default mapping suggestions are included in FOLIO, but libraries will want to review these and customize them to best suit institutional needs.
Default MARC bibliographic → Instance mappings can be found via the MARC Mappings page.
Holdings data
As with Instances, the native FOLIO format for holdings is not MARC. FOLIO implementers should first decide what format they prefer for holdings data. MARC holdings data can be mapped to Inventory but will need to be edited in another app or tool (such as MARCcat). The FOLIO holdings data are granular enough that basic textual holdings can be generated for export in MARC, but do not include, for instance, captions and patterns that are distinct from enumeration and chronology.
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