Encoded Archival Description (EAD) is a set of rules for designating the intellectual and physical parts of archival finding aids so that the information contained therein may be searched, retrieved, displayed, and exchanged in a predictable platform-independent manner. The EAD rules are written in the form of a Standard Generalized Markup Language (SGML) Document Type Definition (DTD), which uses coded representations of elements for efficient machine-processing by SGML authoring and viewing software. Because DTDs are intended to be read chiefly by computers, they are often accompanied by documentation designed for human comprehension. This tag library or master list of elements is one such piece of documentation. It serves as a reference tool for archivists who need to decide which EAD elements to use when designating the content of their organizations' finding aids. Through the use of natural-language definitions and examples, it assists archivists in achieving effective and consistent markup by rendering EAD's SGML codes more understandable. Despite translating SGML terminology and concepts into a more accessible and familiar language, the tag library is still a technical document that presupposes readers will possess a minimal understanding of SGML and finding aids. Novice finding aid encoders will need to supplement their use of the tag library by consulting EAD application guidelines, attending introductory EAD workshops and institutional training classes, and referring to other information sources. (1)
As a natural-language translation of the EAD DTD, the tag library conveys information about the three principal tasks accomplished by the DTD. First, the EAD DTD breaks down the content of finding aids into data fields or categories of information called "elements." All of these elements are named, defined, and described in the EAD Tag Library. Secondly, the tag library identifies and defines any attributes that the DTD has associated with those elements. Attributes are characteristics or properties that further refine the element designation. Lastly, and perhaps most importantly, the tag library expresses the DTD structure by explaining the relationship between elements, specifying where the elements may be used and describing how they may be modified with attributes. While two of the basic purposes of EAD are to faciliate the searching and display of encoded finding aids in an electronic environment, nothing in the Tag Library itself addresses their specific implementation. Searching and display are instead dependent entirely on individual software applications and the stylesheets generally associated with such software.
Throughout the tag library, snippets of encoded finding aids augment the narrative explanations and help illustrate the role, relationship, and usage of elements and attributes. The tag library includes examples of full tagging to indicate the ways in which elements and attributes can be combined, but less tagging is also possible and even desirable in many situations. The EAD DTD contains only a few required elements; the rest are optional.(2) The amount of markup selected will vary from one repository to another depending on intellectual and financial considerations. Creating finding aids for union databases may also result in tagging requirements that are separate from those dictated by the DTD.(3)
The tag library is divided into six sections. It begins with the EAD Design Principles. This is followed by an overview of the EAD structure and then an explanation of terms and conventions used in the tag library. An attribute list appears next, providing definitions and possible values for all EAD attributes. Element definitions and descriptions comprise the fifth and largest section of the tag library, and an index by element name concludes the documentation.(4)
EAD Version 1.0 is compatible with the new Extensible Markup Language (XML) applications being developed for the World Wide Web as well as with current SGML software. The EAD linking elements follow approaches suggested by a proposed Extended Linking Language (XLink). As the XLink standards evolve, the attributes on EAD's linking elements can be revised in future EAD versions. Suggestions for new elements or revised descriptions can be submitted to the EAD Working Group via the EAD listserv (See the EAD home page at <//www.loc.gov/ead/> for information on subscribing to the EAD listserv).
Table of Contents | ||||||||
Home Page |
Acknowledgments | Introduction | EAD Design Principles |
Overview of EAD Structure |
Tag Library Conventions |
EAD Attributes | Index of EAD Element Names |
Go to:
The Library of Congress