Network Working Group J. Kunze
Request for Comments: 5013 University of California
Obsoletes: 2413 T. Baker
Category: Informational Dublin Core Metadata Initiative
August 2007
The Dublin Core Metadata Element Set
Status of This Memo
This memo provides information for the Internet community. It does
not specify an Internet standard of any kind. Distribution of this
memo is unlimited.
Abstract
This document defines fifteen metadata elements for resource
description in a cross-disciplinary information environment.
1. Introduction
The Dublin Core Metadata Workshop Series began in 1995 with an
invitational workshop that brought together librarians, digital
library researchers, content experts, and text-markup experts to
promote better discovery standards for electronic resources. The
resulting metadata element set defines fifteen metadata elements for
resource description in a cross-disciplinary information environment.
This document contains the current text of Dublin Core "Version 1.1".
Version 1.1 is the basis of ANSI/NISO Z39.85-2001 [Z39.85]. The text
in the present RFC closely follows the text in the 2007 revision of
ANSI/NISO Z39.85, especially Sections 2-6 and 10-12 [Z39.85-2007].
The present RFC obsoletes RFC 2413 [RFC2413], which was the first
published version of the Dublin Core ("Version 1.0"). The main
differences between the present RFC and RFC 2413 are in the wording
of definitions -- for Contributor and Date (semantically broadened),
for Relation (clarified), and in the general removing of redundant
references to "the content of" a resource. In addition, the present
RFC recommends lowercase element names (consistent with RDF property
types), remains silent about the unrestrictedness of element ordering
and repeatability (application profiles being the proper place to
discuss such topics), and references the current abstract model,
vocabularies, and namespace policies in which the Dublin Core is
embedded.
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2. Foreword
The Dublin Core Metadata Element Set is a vocabulary of fifteen
properties for use in resource description. The name "Dublin" is due
to its origin at a 1995 invitational workshop in Dublin, Ohio; "core"
because its elements are broad and generic, usable for describing a
wide range of resources.
The fifteen element "Dublin Core" described in this document is part
of a larger set of metadata vocabularies and technical specifications
maintained by the Dublin Core Metadata Initiative (DCMI). The full
set of vocabularies, DCMI Metadata Terms [DCTERMS], also includes a
set of resource classes, the DCMI Type Vocabulary [DCTYPE]. The
terms in DCMI vocabularies are intended to be used in combination
with terms from other compatible vocabularies in the context of
application profiles and on the basis of the DCMI Abstract Model
[DCAM].
All changes made to terms of the Dublin Core Metadata Element Set
since 2001 have been reviewed by a DCMI Usage Board in the context of
a DCMI Namespace Policy [DCNMSPC]. The namespace policy describes
how DCMI terms are assigned Uniform Resource Identifiers (URIs) and
sets limits on the range of editorial changes that may allowably be
made to the labels, definitions, and usage comments associated with
existing DCMI terms.
3. Scope and Purpose
The Dublin Core Metadata Element Set is a standard for cross-domain
resource description. As in RFC 3986 [RFC3986], "Uniform Resource
Identifier (URI): Generic Syntax", this specification does not limit
the scope of what might be a resource.
The elements described in this document are typically used in the
context of an application profile which constrains or specifies their
use in accordance with local or community-based requirements and
policies. The specification of such implementation detail is outside
the scope of this document.
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RFC 5013 Dublin Core Metadata August 2007
4. Definitions
DCMI -- the Dublin Core Metadata Initiative, maintenance agency for
Dublin Core Metadata Element Set.
Resource -- anything that might be identified (the same definition as
in RFC 3986 and in the DCMI Abstract Model).
Lifecycle of a resource -- a sequence of events that mark the
development and use of a resource. Some examples of events in a
lifecycle are: conception of an invention, creation of a draft,
revision of an article, publication of a book, acquisition by a
library, transcription to magnetic disk, migration to optical
storage, translation into English, and derivation of a new work
(e.g., a movie).
5. The Element Set
In the element descriptions below, each element has a descriptive
label ("label") for human consumption and a unique token ("name") for
use in machine processing.
In accordance with the DCMI Namespace Policy [DCNMSPC], the "name" of
an element is appended to a DCMI namespace URI to construct a Uniform
Resource Identifier as a globally unique identifier for that element.
The use of element names and URIs in the context of different
implementation technologies is explained in DCMI Encoding Guidelines
[DCENCOD].
6. The Elements
Element Name: title
Label: Title
Definition: A name given to the resource.
Element Name: creator
Label: Creator
Definition: An entity primarily responsible for making the resource.
Comment: Examples of a Creator include a person, an organization,
or a service. Typically, the name of a Creator should
be used to indicate the entity.
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Element Name: subject
Label: Subject
Definition: The topic of the resource.
Comment: Typically, the subject will be represented using
keywords, key phrases, or classification codes.
Recommended best practice is to use a controlled
vocabulary. To describe the spatial or temporal
topic of the resource, use the Coverage element.
Element Name: description
Label: Description
Definition: An account of the resource.
Comment: Description may include but is not limited to:
an abstract, a table of contents, a graphical
representation, or a free-text account of
the resource.
Element Name: publisher
Label: Publisher
Definition: An entity responsible for making the resource available.
Comment: Examples of a Publisher include a person, an
organization, or a service. Typically, the name of
a Publisher should be used to indicate the entity.
Element Name: contributor
Label: Contributor
Definition: An entity responsible for making contributions to the
resource.
Comment: Examples of a Contributor include a person, an
organization, or a service. Typically, the name of a
Contributor should be used to indicate the entity.
Element Name: date
Label: Date
Definition: A point or period of time associated with an event
in the lifecycle of the resource.
Comment: Date may be used to express temporal information
at any level of granularity. Recommended best
practice is to use an encoding scheme, such as
the W3CDTF profile of ISO 8601 [W3CDTF].
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Element Name: type
Label: Type
Definition: The nature or genre of the resource.
Comment: Recommended best practice is to use a controlled
vocabulary such as the DCMI Type Vocabulary
[DCTYPE]. To describe the file format, physical medium,
or dimensions of the resource, use the Format element.
Element Name: format
Label: Format
Definition: The file format, physical medium, or dimensions
of the resource.
Comment: Examples of dimensions include size and duration.
Recommended best practice is to use a controlled
vocabulary such as the list of Internet Media Types
[MIME].
Element Name: identifier
Label: Identifier
Definition: An unambiguous reference to the resource within a given
context.
Comment: Recommended best practice is to identify the
resource by means of a string conforming
to a formal identification system.
Element Name: source
Label: Source
Definition: A related resource from which the described resource
is derived.
Comment: The described resource may be derived from the
related resource in whole or in part. Recommended
best practice is to identify the related resource
by means of a string conforming to a formal
identification system.
Element Name: language
Label: Language
Definition: A language of the resource.
Comment: Recommended best practice is to use a controlled
vocabulary such as RFC 4646 [RFC4646].
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Element Name: relation
Label: Relation
Definition: A related resource.
Comment: Recommended best practice is to identify the
related resource by means of a string conforming
to a formal identification system.
Element Name: coverage
Label: Coverage
Definition: The spatial or temporal topic of the resource, the
spatial applicability of the resource, or the
jurisdiction under which the resource is relevant.
Comment: Spatial topic and spatial applicability may be a named
place or a location specified by its geographic
coordinates. Temporal topic may be a named period,
date, or date range. A jurisdiction may be a named
administrative entity or a geographic place to which the
resource applies. Recommended best practice is to use a
controlled vocabulary such as the Thesaurus of
Geographic Names [TGN]. Where appropriate, named places
or time periods can be used in preference to numeric
identifiers such as sets of coordinates or date ranges.
Element Name: rights
Label: Rights
Definition: Information about rights held in and over the resource.
Comment: Typically, rights information includes a statement about
various property rights associated with the resource,
including intellectual property rights.
7. Security Considerations
The Dublin Core element set poses no risk to computers and networks.
It poses minimal risk to searchers who obtain incorrect or private
information due to careless mapping from rich data descriptions to
the Dublin Core elements. No other security concerns are likely.
10. Informative References
[DCAM] DCMI Abstract Model.
http://dublincore.org/documents/abstract-model/
[DCENCOD] DCMI Encoding Guidelines.
http://dublincore.org/resources/expressions/
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[DCNMSPC] DCMI Namespace Policy.
http://dublincore.org/documents/dcmi-namespace/
[DCTERMS] DCMI Metadata Terms.
http://dublincore.org/documents/dcmi-terms/
[DCTYPE] DCMI Type Vocabulary.
http://dublincore.org/documents/dcmi-type-vocabulary/
[ISO3166] ISO 3166 - Codes for the representation of names of
countries. http://www.din.de/
[MIME] Internet Media Types.
http://www.iana.org/assignments/media-types/
[RDF] Resource Description Framework. http://www.w3.org/RDF/
[RFC2413] Weibel, S., Kunze, J., Lagoze, C., and M. Wolf, "Dublin
Core Metadata for Resource Discovery", RFC 2413,
September 1998.
[RFC2731] Kunze, J., "Encoding Dublin Core Metadata in HTML", RFC
2731, December 1999.
[RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter,
"Uniform Resource Identifier (URI): Generic Syntax",
STD 66, RFC 3986, January 2005.
[RFC4646] Phillips, A. and M. Davis, "Tags for Identifying
Languages", BCP 47, RFC 4646, September 2006.
[TGN] Getty Thesaurus of Geographic Names.
http://www.getty.edu/research/tools/vocabulary/
tgn/index.html
[W3CDTF] Date and Time Formats, W3C Note.
http://www.w3.org/TR/NOTE-datetime
[Z39.85] ANSI/NISO Standard Z39.85-2001 - The Dublin Core
Metadata Element Set.
http://www.niso.org/standards/resources/Z39-85.pdf
[Z39.85-2007] ANSI/NISO Standard Z39.85-2007 - The Dublin Core
Metadata Element Set.
http://www.niso.org/standards/resources/Z39-85-2007.pdf
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Appendix A: Further Reading
(This appendix is not part of the Z39.85 standard. It is included
for information only.)
Further information about the Dublin Core metadata element set is
available at the URL,
http://dublincore.org/
This Web site contains information about workshops, reports, working
group papers, projects, and new developments concerning the Dublin
Core Metadata Initiative (DCMI).
Appendix B: Maintenance Agency
(This appendix is not part of the Z39.85 standard. It is included
for information only.)
The Dublin Core Metadata Initiative (DCMI) is responsible for the
development, standardization, and promotion of the Dublin Core
metadata element set. Information on DCMI is available at the URL,
http://dublincore.org/
Authors' Addresses
John A. Kunze
California Digital Library
University of California, Office of the President
415 20th St, 4th Floor
Oakland, CA 94612-3550, USA
Fax: +1 510-893-5212
EMail: jak@ucop.edu
Thomas Baker
Director, Specifications and Documentation
Dublin Core Metadata Initiative
c/o OCLC Research
Dublin, OH 43017, USA
EMail: tbaker@tbaker.de
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Kunze & Baker Informational [Page 9]
