- Encoded Archival Description
Encoded Archival Description is an
XML standard for encoding archivalfinding aid s, maintained by theLibrary of Congress in partnership with theSociety of American Archivists .History
EAD originated in
1993 , at theUniversity of California, Berkeley . The project's goal was to create a standard for describing collections held byarchive s andspecial collections , similar to theMARC standards for describing regular books. Such a standard enablesmuseum s,libraries , and manuscript repositories to list and describe their holdings in a manner that would be machine-readable and therefore easy to search, maintain, exchange. Since its inception manyspecial collections andarchives have adopted it.In addition to the development and maintenance work done by the Society of American Archivists and the Library of Congress, the
Research Libraries Group (RLG) has developed and published a set of "Best Practices" implementation guidelines for EAD, which lays out mandatory, recommended, and optional elements and attributes. RLG has also provided a kind of clearinghouse for finding aids in EAD format, known as "ArchiveGrid." Member libraries provide RLG the URL for their finding aids; RLG automatically harvests data from the finding aids, indexes it, and provides a search interface for the index, thus giving researchers the ability to search across several hundred institutions' collections with a single query. RLG also has developed the "RLG Report Card," an automated quality-checking program that will analyze an EAD instance and report any areas where it diverges from the best practices guidelines.Adoption
A number of repositories in the United States, England, Australia and elsewhere have adopted and implemented EAD with varying levels of technical sophistication. A list of implementors is available [http://www.archivists.org/saagroups/ead/implementors.html here] . Perhaps the most ambitious effort is the [http://www.oac.cdlib.org/ Online Archive of California] , a
union catalog of over 5000 EAD finding aids covering manuscripts and images from institutions across the state.EAD DTD
The EAD standard's
document type definition (DTD) specifies the elements to be used to describe a manuscript collection as well as the arrangement of those elements (for example, which elements are required, or which are permitted inside which other elements). EAD 1.0 was anSGML DTD; EAD 2002, the second and current incarnation of EAD, was finalized in December 2002 and is anXML DTD. The EAD tag set has 146 elements and is used both to describe a collection as a whole, and also to encode a detailed multi-level inventory of the collection. Many EAD elements have been, or can be, mapped to other standards such as MARC orDublin Core , increasing the flexibility andinteroperability of the data.Parts of an EAD finding aid
eadheader
The first section of an EAD-encoded finding aid is the
eadheader
. This section contains thetitle
and optionalsubtitle
of the collection and detailed information about the finding aid itself: who created it, when it was created, itsrevision history , the language the finding aid is written in, and so on. Theeadheader
itself has a number of required attributes that map to variousISO standards such asISO 3166-1 for country codes andISO 8601 for date formats.The
eadheader
and its child elements can be mapped to other standards for easy interchange of information. They are often mapped to Dublin Core elements such as Creator, Author, Language. For example, in the excerpt below therelatedencoding="DC"
attribute of theeadheader
element specifies that child elements will be mapped to Dublin Core; the child element
indicates that the EAD element
maps to the Dublin Core element
.Example of an eadheader:
archdesc
The
archdesc
section contains the description of the collection material itself. First, the "data item description" ordid
element contains a description of the collection as a whole, including the creator (which may be an individual or an organization), size (usually given inlinear feet ), inclusive dates, language(s), and an abstract or brief description. As with theeadheader
above, elements may be mapped to correspondeing standards; elements in this section are usually mapped to MARC elements. For example, in the excerpt below therelatedencoding="MARC21"
attribute of thearchdesc
element specifies that child elements will be mapped to MARC21; the child element
indicates that theunittitle
element maps to MARC field 245, subfield a.Example:
Several additional descriptive elements may follow the
did
including:*
bioghist
- biographic description of the person or organization
*scopecontent
- a detailednarrative description of the collection material
*relatedmaterial
- description of items which the repository acquired separately but which are related to this collection, and which a researcher might want to be aware of
*separatedmaterial
- items which the repository acquired as part of this collection but which have been separated from it, perhaps for special treatment, storage needs, or cataloging
*controlaccess
- a list of subject headings or keywords for the collection, usually drawn from an authoritative source such asLibrary of Congress Subject Headings or theArt and Architecture Thesaurus
*accessrestrict
anduserestrict
- statement concerning any restrictions on the material in the collectionThe second, and usually largest, section of the
archdesc
is thedsc
, which contains a full inventory of the collection broken down into progressively smaller intellectual chunks. EAD offers two options: thec
element which can be nested within itself to an unlimited level, and a set of numbered container elementsc01
throughc012
which can only be nested numerically (i.e. ac01
can contain only ac02
; ac02
can contain only ac03
, and so on). Note that thec
andc0#
elements refer to "intellectual" subdivisions of the material; the actual physical container is specified using thecontainer
element. The inventory may go down to as detailed a level as desired. The example below shows an inventory to the folder level.Example of an inventory:
ee also
*
Encoded Archival Context (EAC)External links
* [http://archivegrid.org ArchiveGrid]
* [http://www.loc.gov/ead/ EAD Version 2002 official home page]
* [http://www.archivists.org/saagroups/ead/ EADToolsSurvey.pdf EAD Tools Survey]
* [http://www.oac.cdlib.org/ Online Archive of California]
* [http://www.rlg.org/en/pdfs/bpg.pdf RLG Best Practices Guidelines for Encoded Archival Description]
* [http://www.rlg.org/ead-report-card/ RLG EAD Report Card]
* [http://www.archivists.org/ Society of American Archivists]
* [http://www.archiviststoolkit.org/ Archivist's Toolkit]
* [http://www.archon.org Archon]
* [http://www.calames.abes.fr Calames] , French universities archives and manuscripts catalog
* [http://archivopedia.com/_mgxroot/page_10753.html EAD Central Search]
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