The Dublin Core Metadata Initiative (DCMI) has written multiple specifications:
- The Dublin Core Metadata Element Set, as defined at http://purl.org/dc/elements/1.1/
- Other Elements and Element Refinements, as defined at http://purl.org/dc/terms/
- Encoding Schemes, as defined at http://purl.org/dc/terms/
- The DCMI Type Vocabulary, as defined at http://purl.org/dc/dcmitype/
Use in RDF documents
Dublin Core was primarily designed to be used in RDF documents. It allows you to make statements like:
<rdf:RDF xmlns:dc="http://purl.org/dc/elements/1.1"> <dc:Document rdf:about="http://www.example.org/mydocument.html"> <dc:creator>John Doe</dc:creator> </dc:Document>
See RDF schemas for other schemas.
Use in HTML metadata
To use Dublin Core for HTML metadata, only these specifications are relevant:
- The Dublin Core Metadata Element Set, as formally defined at http://purl.org/dc/elements/1.1/
- Element Refinements, as formally defined (amongst others) at http://purl.org/dc/terms/
Note that the refinements, like created, are intended to be used with the base term. For example, dcterm:created is a refinement of dc:date, creating date.created. Such a refinement can be specified in these two, equivalent, ways:
<meta name="DC.date.created" content="2001-07-18" /> <meta name="DCTERMS.created" content="2001-07-18" />
See the HTML Metadata article for more information how to define meta-data in HTML documents.
You need to specify the URI of the formal definitions if you define the namespace. The human readable description can be found at http://dublincore.org/documents/dcmi-terms/.
Dublin Core Elements
The Dublin Core Element Set v1.1 defines:
- The person, organisation, or service responsible for making contributions to the content of the resource
- The extent or scope of the content of the resource, like geographic location, date range or jurisdiction.
- The person, organisation, or service primarily responsible for making the content of the resource.
- A date associated with an event in the life cycle of the resource. Typically, the creation date.
- An account of the content of the resource, like abstract, or table of contents.
- The physical or digital manifestation of the resource. For electronic formats, recommended practice is to use a MIME type.
- An unambiguous reference to the resource within a given context, like URL or URN. For example "urn:ISBN:8884530431"
- A language of the intellectual content of the resource. Recommended practice is to derive a value from RFC 3066 and ISO 639 (e.g. "en" or "en-GB")
- An entity responsible for making the resource available.
- A reference to a related resource.
- Information about rights held in and over the resource. This may include copyright, intellectual property rights, or license.
- A reference to a resource from which the present resource is derived. See also the relation refinements.
- The topic of the content of the resource. Recommended is to specify multiple subject lines, each with a separate keyword.
- A name given to the resource.
- The nature or genre of the content of the resource. Recommended is to use the DCMI Type Vocabulary for values.
Dublin Core Terms
The Dublin Core Terms Namespace defines:
- A class of entity for whom the resource is intended or useful.
- A general statement describing the education or training context. Alternatively, a more specific statement of the location of the audience in terms of its progression through an education or training context.
- Spatial (geographic location) characteristics of the content of the resource.
- Date or time range related to the content of the resource.
- Date (often a range) that the resource will become or is available.
- Date of creation of the resource.
- Date on which the resource was changed.
- Date of a statement of copyright.
- Date of submission of the resource (e.g. thesis, articles, etc.).
- Date of acceptance of the resource (e.g. of thesis by university department, of article by journal, etc.).
- Date of formal issuance (e.g., publication) of the resource.
- Date (often a range) of validity of a resource.
- A summary of the content of the resource.
- A list of subunits of the content of the resource.
- The size or duration of the resource.
- A bibliographic reference for the resource. Recommended is to make this an extensive plain text field, and use identifier for URI, ISBN, etc.
- A statement of any changes in ownership and custody of the resource since its creation that are significant for its authenticity, integrity and interpretation.
- A reference to an established standard to which the resource conforms.
- The described resource pre-existed the referenced resource, which is essentially the same intellectual content presented in another format.
- The described resource is the same intellectual content of the referenced resource, but presented in another format. See also the standard alternative keyword.
- The described resource includes the referenced resource either physically or logically.
- The described resource is a physical or logical part of the referenced resource.
- The described resource has a version, edition, or adaptation, namely, the referenced resource.
- The described resource is a version, edition, or adaptation of the referenced resource.
- The described resource references, cites, or otherwise points to the referenced resource.
- The described resource is referenced, cited, or otherwise pointed to by the referenced resource.
- The described resource supplants, displaces, or supersedes the referenced resource.
- The described resource is supplanted, displaced, or superseded by the referenced resource.
- The described resource requires the referenced resource to support its function, delivery, or coherence of content.
- The described resource is required by the referenced resource, either physically or logically.
- Information about who can access the resource or an indication of its security status.
- A legal document giving official permission to do something with the resource. Recommended best practice is to identify the license using a URI.
- A person or organization owning or managing rights over the resource.
- Any form of the title used as a substitute or alternative to the formal title of the resource, including abbreviations and translations.
In addition, the terms namespace defines accrualMethod , accrualPeriodicity, accrualPolicy, audience, instructionalMethod, audience.mediator, and format.medium. These terms do not seem very useful to me.