Metadata Object Description Schema (MODS) Available for Trial Use
The Library of Congress' Network Development and MARC Standards Office, with interested experts, has developed the Metadata Object Description Schema (MODS) , which is a bibliographic element set that may be used for a variety of purposes, particularly for library applications. Information about MODS and the schema (version 1.2) is available at:
As an XML schema it is intended to be able to carry selected data from existing MARC 21 records as well as to enable the creation of original resource description records. It includes a subset of MARC fields and uses language-based tags rather than numeric ones, in some cases regrouping elements from the MARC 21 bibliographic format. The elements inherit MARC semantics, so are more compatible with existing library data than other metadata schemes.
MODS could potentially be used as follows:
- as a Z39.50 Next Generation specified format
- as an extension schema to METS (Metadata Encoding and Transmission Standard)
- to represent metadata for harvesting
- for original resource description in XML syntax (using MARC semantics)
- for representing a simplified MARC record in XML
- for metadata in XML that may be packaged with an electronic resource
MODS includes a subset of data from the MARC 21 Format for Bibliographic Data. As an element set that allows for the representation of data already in MARC-based systems, it is intended to allow for the conversion of core fields from a MARC 21 record, while some specific data may be dropped. As an element set for original resource description, it allows for a simple record to be created, in some cases using more general tags than those available in the MARC record. The Library of Congress has developed transformations to move MARC 21 records from 2709 form to MARCXML to MODS, with the software available from the MARCXML Web site.
There has been wide review and input to the development of the schema, which is now available for trial use. It will remain stable for the next six months, during which we invite comments as a result of experimentation.
For questions or comments please email the Office at firstname.lastname@example.org.
Sally McCallum, Chief
Network Development and MARC Standards Office
Library of Congress, Washington, DC, USA
Prepared by Robin Cover for The XML Cover Pages archive. See: (1) "Library of Congress Publishes MARC 21 XML Schema and Transformation Tools"; (2) "MARC (MAchine Readable Cataloging) and SGML/XML."