Dublin Core:
Elements & Uses
Source: The Dublin Core Metadata Initiative Home Page, <http://dublincore.org>.
Jody DeRidder
IS 565, Digital Libraries
Dr. Suzie Allard, Professor
February 14, 2007
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CONTENTS
PAGE
OVERVIEW . . . . . . . . . . . . . . . . . . . . 1
THE 15 DUBLIN CORE ELEMENTS . . . . . . . . . 2
Instantiation Elements . . . . . . . . . . . . . . 2
Language
Identifier
Date
Format
Content Elements . . . . . . . . . . . . . . . . 3
Title
Description
Subject
Coverage
Source
Type
Relation
Intellectual Property Elements . . . . . . . . . . . 3
Creator
Contributor
Publisher
Rights
QUALIFIERS AND THE “DUMB DOWN” PRINCIPLE . . 4
Element Refinements
Encoding Schemes
USES FOR THE DC ELEMENT SET . . . . . . . . . 5
APPENDICES . . . . . . . . . . . . . . . . . . . 6
Quiz Questions . . . . . . . . . . . . . . . . . 6
Vocabulary Terms . . . . . . . . . . . . . . . . 7
Sample Dublin Core Record . . . . . . . . . . . . 8
BIBLIOGRAPHY . . . . . . . . . . . . . . . . . . 9
OVERVIEW
The Dublin Core Metadata Initiative developed fifteen elements and several qualifiers, for
use in describing resources. An element is a characteristic of the resource (or a metadata
field), and a resource is anything that has an identity, such as a book or a photograph. Any
element may be used as many or as few times as needed; there is no order to their use. The
schema must be referenced at the top of the file. (The schema details what elements may be
used and how.) The fifteen elements can be divided by the type of information they are
intended to provide. The three divisions are Instantiation, Content, and Intellectual Property.
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THE 15 DUBLIN CORE ELEMENTS
Instantiation Elements
An instantiation is “a specific occurrence of an information resource.” Examples of
multiple instantiations would be: two images of the same object, or a text translated into
English and into French, or a video and a still image of a museum piece. Each instantiation
requires a separate application of the elements (therefore, a separate metadata record).
The four elements for Instantiation are:
1) Language: the language of the intellectual content of the resource. Recommended best
practice is defined by RFC 1766 (Tags for the Identification of Languages) which
includes a 2-letter Language Code (from the ISO 639 standard, Codes for the
representation of names of languages) followed optionally by a two letter country code
(from the ISO 3166 standard, Codes for the representation of the names of countries
2) Identifier: An unambiguous reference to the resource within a given context.
Recommended best practice is to identify the resource by means of a string conforming to
a formal identification system, such as an ISBN.
3) Date: A date associated with the creation or availability of the resource. Recommended
best practice is defined in a profile of ISO 8601 that includes (among others) dates of the
forms YYYY and YYYY-MM-DD.
4) Format: The file format, physical medium, or dimensions of the resource. 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). Example: image/jpeg.
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Content Elements
5) Title: The name given to the resource.
6) Description: An account of the content of the resource. Description may include but is
not limited to: an abstract, table of contents, reference to a graphical representation of
content or a free-text account of the content.
7) Subject: The topic of the content of the resource. Typically, a subject will be expressed
as keywords or key phrases or classification codes that describe the topic of the resource.
8) Coverage: The extent or scope of the content of the resource. Coverage will typically
include spatial location (a place name or geographic co-ordinates), temporal period (a
period label, date, or date range) or jurisdiction (such as a named administrative entity).
9) Source : A reference to a resource from which the present resource is derived. The
present resource may be derived from the Source resource in whole or part.
10) Type: The nature or genre of the content of the resource. Type includes terms describing
general categories, functions, genres, or aggregation levels for content.
11) Relation: A reference to a related resource.
Intellectual Property Elements
12) Creator: An entity primarily responsible for making the content of the resource.
Examples of a Creator include a person, an organization, or a service.
13) Contributor: An entity responsible for making contributions to the content of the
resource. 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.
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14) Publisher: The entity responsible for making the resource available. 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.
15) Rights: Information about rights held in and over the resource. Typically a Rights
element will contain a rights management statement for the resource, or reference a
service providing such information. Rights information often encompasses Intellectual
Property Rights, Copyright, and various Property Rights.
QUALIFIERS AND THE “DUMB DOWN” PRINCIPLE
Qualifiers are terms that refine the Dublin Core Elements. According to the “Dumb
Down” principle, the client should be able to ignore a qualifier and use the value as if it were
unqualified. There are two classes of qualifiers: Element Refinements, and Encoding
Schemes.
Type Of
Element
Example Qualifiers
Element
Description
Abstract, tableOfContents
Refinement
Coverage
Spatial, Temporal
Date
Available, Created, dateCopyrighted, dateAccepted,
Qualifier
dateSubmitted
Relation
hasPart, hasVersion, isPartOf, isReferencedBy, isReplacedby,
isVersionOf
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Encoding
Subject
DDC (Dewey Decimal Classification),
LCC (Library of Congress Classification),
Schemes
LCSH (Library of Congress Subject Headings),
MESH (Medical Subject Headings)…
Language
ISO639-2 (such as eng, for English),
RFC1766 (such as en-us for US English)
Date
W3CDTF (such as 1997-12-04 for December 4, 1997)
Type
DCMIType, such as: Collection, Dataset, Event, Image,
InteractiveResource, MovingImage, PhysicalObject, Service,
Software, Sound, StillImage, Text.
USES FOR THE DC ELEMENT SET
In general, the set of Dublin Core elements is used to create records for resources so that
those resources can be searched for and retrieved using those elements to identify the type of
information sought (for example: to be able to search documents with “Civil War” as a subject).
So you will see the elements in XML for computer processing, and as labels of fields to search in
an interface (the results of that processing).
Some of the areas of current use are in Web Feeds, such as RSS, in HTML meta and link
elements for web pages, and in RDF for semantic web applications. In addition, the Dublin Core
elements are widely used in digital libraries, to create records for resources (example here).
They often form the common denominator for federated digital libraries, such as those comprised
of metadata records for the Open Archives Initiative. A primary example of this use can be seen
in OAIster, a massive database of over 10 million records of digital scholarly materials.
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APPENDICES
Quiz Questions
1) What is the “Dumb-Down” principle?
The qualification of Dublin Core Elements is guided by a rule known colloquially as the
Dumb-Down Principle. According to this rule, a client should be able to ignore any qualifier
and use the value as if it were unqualified. While this may result in some loss of specificity,
the remaining term value (minus the qualifier) must continue to be generally correct and
useful for discovery. Qualification is therefore supposed only to refine, not extend the
semantic scope of an Element.
2) What is the DCMI Type Vocabulary? Give three examples.
The DCMI Type Vocabulary is a general, cross-domain list of approved terms that may be
used as values for the Resource Type (dc:type) element to identify the genre of a resource.
Examples: Collection, Dataset, Event, Image, InteractiveResource, MovingImage,
PhysicalObject, Service, Software, Sound, StillImage, Text.
3) What are Dublin Core "Qualifiers"?
Dublin Core Qualifiers are terms that extend or refine the original 15 elements of the
Dublin Core Metadata Element Set. There are two broad classes of qualifiers: Element
Refinement and Encoding Scheme. Qualifiers must follow the "Dumb-Down" principle.
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Vocabulary Terms
1) Element Refinement: A refinement shares the meaning of the DCMI element, but with a
more restricted scope, or narrower semantic meaning.
2) "Instantiation" (in Dublin Core)
An instantiation is a specific occurrence of an information resource.
Example: a particular scan of a musical score, of which there may be many versions.
3) Encoding Scheme:
An encoding scheme aids in the interpretation of the element value, by referring the user to the
controlled vocabulary, formal notation, or the parsing rules used.
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Sample Dublin Core record,
created by Melanie Feltner-Reichert, Metadata Librarian, for the University of Tennessee
Libraries Arrowmont Project. This record is currently viewable online here courtesy of the
University of Tennessee Digital Library Center.
<record xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:dcterms="http://purl.org/dc/terms/">
<dc:title> An Impression of the Pi Beta Phi Settlement School and its Vicinity</dc:title>
<dc:creator> Moorehead, Rosemary</dc:creator>
<dcterms:dateCreated> 1936-11-07</dcterms:dateCreated>
<dc:type> Mixed material</dc:type>
<dc:type> Scrapbook</dc:type>
<dc:format xsi:type="dcterms:IMT"> image/jpeg</dc:format>
<dc:description> Scrapbook on the Pi Beta Phi Settlement School and Gatlinburg area.
Compiled by Pi Beta Phi teacher Rosemary Moorehead. </dc:description>
<dc:subject> Student life</dc:subject>
<dc:subject> Settlement schools </dc:subject>
<dc:subject> Gatlinburg, Tennessee</dc:subject>
<dc:subject> Pi Beta Phi Settlement School</dc:subject>
<dc:subject> Expansion and Growth of Pi Beta Phi Settlement School, 1928-1943</dc:subject>
<dc:source> Great Smoky Mountains Regional Project, The University of Tennessee
Libraries. </dc:source>
<dc:rights> For rights relating to this resource, visit:
http://idserver.utk.edu/?id=200500000001941</dc:rights>
<dc:identifier> rms00000</dc:identifier>
<dc:relation> From Pi Beta Phi to Arrowmont:
http://idserver.utk.edu/?id=200500000001049</dc:relation>
<dc:language xsi:type="dcterms:ISO639-2"> eng</dc:language>
</record>
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BIBLIOGRAPHY
Alvestrand, H. “Request For Comments: 1766: Tags for the Identification of Languages.”
Network Working Group, March 1995. <http://www.faqs.org/rfcs/rfc1766.html> (20 January
2007).
Apps, Ann. "Guidelines for Encoding Bibliographic Citation Information in Dublin Core
Metadata.” Dublin Core Metadata Initiative. 13 June 2005.
<http://dublincore.org/documents/dc-citation-guidelines/> (15 January 2007).
Beckett, Dave, Eric Miller, and Dan Brickley. "Expressing Simple Dublin Core in RDF/XML.”
Dublin Core Metadata Initiative, 31 July 2002.
<http://dublincore.org/documents/dcmes-xml/> (15 January 2007).
Beged-Dov, Gabe, Dan Brickley, Rael Dornfest, et.al. “RDF Site Summary 1.0 Modules:
Dublin Core.” Web Resource Organization, 20 December 2000.
<http://web.resource.org/rss/1.0/modules/dc/> (20 January 2007).
DCMI Usage Board. “DCMI Type Vocabulary.” Dublin Core Metadata Initiative, 28 August
2006. < http://dublincore.org/documents/dcmi-type-vocabulary/> (23 January 2007).
--- "Dublin Core Metadata Terms." Dublin Core Metadata Initiative, 18 December 2006.
<http://dublincore.org/documents/dcmi-terms/> (15 January 2007).
Dublin Core Metadata Initiative. “DCMI Term Declarations Represented in XML Schema
Language.” Dublin Core Metadata Initiative, 10 April 2006.
<http://dublincore.org/schemas/xmls/> (23 January 23, 2007).
--- "Dublin Core Metadata Element Set, Version 1.1." Dublin Core Metadata Initiative, 18
December 2006. <http://dublincore.org/documents/dces/> (15 January 2007).
--- "Using Dublin Core - Dublin Core Qualifiers.” Dublin Core Metadata Initiative, 7 November
2005. <http://dublincore.org/documents/usageguide/qualifiers.shtml> (15 January 2007).
Hillman, Diane. “Using Dublin Core.” Dublin Core Metadata Initiative, 12 April
<http://dublincore.org/documents/2001/04/12/usageguide/sectc.shtml> (15 January 2007).
ISO 639 Joint Advisory Committee. "Codes for the Representation of Names of Languages.”
Library of Congress, 6 October 2006.
<http://www.loc.gov/standards/iso639-2/php/code_list.php> (15 January 2007).
Lagoze, Carl and Herbert Van de Sompel, ed. “The Open Archives Initiative Protocol for
Metadata Harvesting,” Version 2.0. The Open Archives Initiative, 14 June 2002,
<http://www.openarchives.org/OAI/openarchivesprotocol.html> (23 January 2007).
Powell, Andy. "Expressing Dublin Core in HTML/XHTML Meta and Link Elements.” Dublin
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Core Metadata Initiative, 30 November 2003. <http://dublincore.org/documents/dcq-html/>
(15 January 2007).
Powell, Andy and Pete Johnston. "Guidelines for implementing Dublin Core in XML.” Dublin
Core Metadata Initiative, 2 April 2003.
<http://dublincore.org/documents/dc-xml-guidelines/> (15 January 2007).
Wolf, Misha, and Charles Wicksteed. “Date and Time Formats.” World Wide Web
Consortium, 27 August 1998. <http://www.w3.org/TR/NOTE-datetime> (20 January
2007).
Woodley, Mary, Gail Clement, and Pete Winn. "DCMI Glossary.” Dublin Core Metadata
Initiative, 7 November 2005. <http://dublincore.org/documents/usageguide/glossary.shtml>
(15 January 2007).