DPLAThe DPLA Metadata Application Profile is the metadata schema that underpins the Digital Public Library of America's aggregation infrastructure. It provides a standardized structure for normalizing metadata contributed by hundreds of libraries, archives, and museums across the United States into a single, searchable index. Based on the Europeana Data Model (EDM), the MAP integrates the specific needs of American cultural heritage institutions.
Background
The MAP was originally developed in 2012 alongside the launch of DPLA and has been updated through several versions: 3.0, 3.1, 4.0, and the current version 5.0. It serves as the basis for how metadata is structured, validated, stored, serialized, and made available through the DPLA API in JSON-LD. The profile reflects the experience gained from aggregating metadata across a diverse network of content and service hubs.
Purpose and Scope
DPLA aggregates metadata from a network of hubs representing America's cultural heritage institutions. The MAP serves as the common denominator into which all contributed metadata is mapped, enabling:
- Cross-collection search and discovery across disparate institutions
- Consistent representation of digital objects and their surrogates
- API access to structured metadata in JSON-LD
- Metadata quality assessment and enrichment
The profile defines classes and properties for representing cultural heritage objects (SourceResource), their digital representations (WebResource), and the aggregation relationship (Aggregation).
Metadata Policy
DPLA maintains a strong commitment to freely shareable metadata. The policy asserts that the vast majority of metadata is not subject to copyright. To the extent that any contributed metadata may be protected, partners have agreed to dedicate it to the public domain under CC0. DPLA itself asserts no rights over its database of metadata and dedicates its contributions to the public domain.
Governance and Maintenance
The MAP is maintained by DPLA staff in collaboration with the DPLA Metadata Working Group, which periodically reviews and updates the metadata quality guidelines. A member meeting in June 2022 discussed updated quality guidelines and future plans.
Notable Implementations
The MAP is the operational standard for the entire DPLA infrastructure, serving the metadata of millions of items from libraries, archives, and museums across the United States.
Related Standards
- Europeana Data Model (europeana-data-model): The MAP is profiled from EDM
- Dublin Core (dublin-core-elements): Foundational element set used within the profile