Glossary of Terms


Used to describe information which is in some sense descriptive of a specific element occurring but not regarded as part of its content. (From: the Text Encoding Initiative's A Gentle Introduction to XML)

Attribute Value

The value assigned to a given attribute. Examples of Attribute and Attribute Value:

<name type="person">

...where "person" equals an attribute value.

Cascading Style Sheets (CSS)

A cascading style sheet (CSS) is a document that specifies the layout and appearance of an HTML document to a web browser. CSS is a recommendation from the World Wide Web Consortium (W3C). For more information, visit the W3C's Cascading Style Sheets home page.

Document Type Declaration

Indicates what type of document follows, such as TEI.2, EAD, etc.

Document Type Definition (DTD)

The DTD defines the structural rules of a type of document. These rules include a complete list of allowable elements and attributes, special character entities, rules for external files (such as images), as well as the hierarchical structure of all elements. Examples of documents type definitions include TEI, EAD, and numerous others.

EAD (Encoded Archival Description)

An encoding standard created within the archival profession. It is designed to present information contained within finding aids. It consists of a tag structure that identifies data elements that exist in a multi-level hierarchy. It assists in data-storage and provides a foundation for the searching and navigation of documents. EAD makes use of a specific DTD and the encoding standard XML.


The technical term used in XML for a textual unit, viewed as a structural component. (From: the Text Encoding Initiative's A Gentle Introduction to XML) Examples may include titles, chapters, sections, poems, stanzas, etc.


A process of transferring text and/or data to a searchable electronic medium and organizing it into specific structural and conceptual elements.


The XSLT namespace specifies the version of the XSLT rules to which the stylesheet conforms. The latest version is correctly cited as:



A validation process whereby a computer application compares a document with its DTD. The validation process ensures that the document conforms to all rules set forth in the DTD.

Reliable Output

From IBM Dictionary of Computing, George McDaniel, McGraw-Hill, 1994.

Reliability: the ability of a functional unit to perform a required function under stated conditions for a stated period of time.

Output: data that has been processed.

"Reliable Output" in relation to encoding seems to refer to the accuracy of the end product as prescribed by the DTD, parser, software, stylesheet, etc. In other words, we can expect the results we want in an encoded document based these factors. A typical scenario is parsing a TEI document using a teixlite DTD. We can expect that, when parsed, the software will tell us, based on the teixlite.dtd, whether or not our encoded document is following this DTD. We know based on the conditions that we have set that we will end up with an accurately encoded teixlite document.

Root element

The main "root" of the document hierarchy. For EAD documents, the root element is:


For TEI Lite documents, the root element is:


All other document elements are subsets of this main root element.

SGML (Standardized General Markup Language)

An international standard (ISO 8879), developed by Charles Goldfarb, and others, to permit text encoding.

Style sheets

A term extended from print publishing to online media, a "style sheet" is a definition of a document's appearance in terms of such elements as:

  • The default typeface, size, and color for headings and body text
  • How front matter (preface, figure list, title page, and so forth) should look
  • How all or individual sections should be laid out in terms of space (for example, two newspaper columns, one column with headings having hanging heads, and so forth)
  • Line spacing, margin widths on all sides, spacing between headings, and so on
  • How many heading levels should be included in any automatically generated Table of Contents
  • Any boilerplate content that is to be included on certain pages (for example, copyright statements)

A style sheet permits changing the structure and appearance of XML data without the need for changing the original source data itself.


An XML encoding feature that describes a discrete component of a document, such as a <title> tag signifying a title in a document.


The Text Encoding Initiative was founded in 1987 to develop guidelines for encoding machine-readable texts of interest to the humanities and social sciences. (From:

TEI Lite

TEI Lite is a DTD that includes only a small subset of the whole TEI tag set, selected to include the most commonly needed tags. (From:

XML (Extensible Markup Language)

XML is an encoding standard that assists in the creation, retrieval, and storage of documents. It is designed to exchange documents electronically. XML is considered a simplified subset of SGML. It consists of a tag structure that identifies specific information within a document.

XSLT (Extensible Stylesheet Language for Transformations)

XSLT is an international standard developed by the World Wide Web Consortium (W3C) to permit the powerful reformatting, transformation and display of XML documents.

XSLT Templates

XSLT templates are a standard feature of XSLT stylesheets. They describe by example, or "match", the sections of the XML document that are to be displayed and transformed.