Glossary of E-Book and XML Terms

This glossary is a work in progress, for use by attendees of the AAUP Annual Conference in June 2010. A one-page handout for the e-book workshop will be created from this list. Please send corrections, additions, and comments to ccosner AT stanford DOT edu. Thank you.

Term Description
ancestor An element that encloses the parent of the current element.
app Short for "application" or program. Formerly used by techies to refer to any program, today app more often refers to programs developed for mobile device OSes. A book app or e-book app is an e-book packaged as an application in order to provide capabilities (animation, interactivity) not available in current e-book readers. In some cases an e-book app is produced simply to provide another sales channel, and the app version provides no more content or capability than the e-book.
application file The source file in which a book is typeset. This has typically been a proprietary format, such as Quark or InDesign.
attribute Variable assigned within an element to alter how it is processed. Zero or more attributes may be placed within an opening tag as name="value" pairs, e.g., <div type="acknowledgments">I wish to thank everyone.</div>
bundling The practice of selling an e-book together with the printed book.
catalog A file that maps generic addresses to local directories.
character entity A code placed in XML text to refer to a special character, such as a list bullet, check mark, or diacritic that is not easily represented in the character set of the document. See also: parameter entity.
character set An XML document must use only one character set, and that set should be declared at the beginning of the document. In fact, to step outside the context of XML for a moment, a single text file of any type may only use one character set. The most basic set is ASCII, which includes only 95 printable characters. Another common set is called Latin-1, which includes 191 printable characters and can fully represent 26 languages. Unicode covers most languages. UTF-8 is a flavor of Unicode.
child An element enclosed by the current element.
chunk To split a large document into smaller parts such as chapters, appendices, articles, etc.
CSS Cascading Style Sheets. CSS gives a web browser instructions on how to format and position HTML elements. It is not required, but is a very efficient way to apply consistent styles, such as font and font size, across several pages or documents.
customization layer A stylesheet to be processed with existing standard stylesheets in order to supercede certain formatting instructions with custom instructions.
DAM Digital Asset Management. Refers to the process of storing files in a repository optimized for archiving, retrieval, and search.
declaration May refer to a doctype declaration, which is placed at the beginning of an xml document, or an entity declaration, which resides in a specfication. One can also declare a namespace.
descendants Elements enclosed by the child elements of the current element.
device Computer, cell phone, tablet, netbook, notebook, or dedicated ebook reader.
disaggregated content Content presented and/or sold outside of its usual context. An article sold separately from a journal subscription is a type of disaggregated content, as is a chapter or section of a book sold or presented separately from the book.
DocBook A DTD maintained by OASIS (Organization for the Advancement of Structured Information Standards). A glossary specific to DocBook can be found here:
DOCTYPE A declaration at the beginning of an XML document that tells you the DTD to be used and the element that will serve as root.
DOI Digital Object Identifier. A unique id registered with and maintained by a linking service such as CrossRef ( A DOI may point to any part of a digital object, but for e-books it typically references the text at the chapter or paragraph level.
DRM Digital Rights Management. Software that prescribes and enforces the viewing time, prevents copying of source files, or otherwise limits what the user or purchaser can do with a digital object.
DTBook DAISY or Digital Talking Book. A DTD maintained by the Daisy Consortium ( DTBoook was originally developed for visually impaired or otherwise handicapped readers. It is now a part of the ePub standard (content of an ePub file may be XHTML or DTBook.)
DTD Document Type Definition. A detailed specification for encoding and producing documents with XML. The DTD specifies which elements are valid, how they can be used, and to some extent, their customary meaning within the document.
Dublin Core A metadata standard for many types of information, maintained by the Dublin Core Metadata Initiative (
ecosystem Refers to a combination of software, hardware, and purchasing options that play well together. Commonly seen are the "Nook ecosystem" or the "Google ecosystem." For example, the "Kindle ecosystem" refers to Amazon's website, the Kindle reading device, and Kindle software that allows you to view Kindle books on other devices. The word seems to connote symbiosis and interaction, as well as the essentially closed nature of these systems. The user buys into, accepts, or can easily enter the ecosystem once they commit to a single part of that system. This encourages them to stay in a particular ecosystem for future purchases.
element Part of an XML document enclosed by an opening tag <tei> and a closing tag </tei>. Elements can be nested within each other. The root element is the first element of the document, and whose tags enclose the entire document, excluding declarations at the very beginning..
embedded font In order to be sure that a font is available when a file is opened on another system, one can embed the font in the file. Word documents, PDFs, e-books, and even web pages can have embedded fonts. There may be license, platform- or OS-compatibility, and/or display issues when using an embedded font.
entity An organization, company, or individual associated with the document, generally referred to in the DOCTYPE declaration (DocBook version 5) or DTD. See also: character entity.
ePub A standard e-book format, supported by the International Digital Publishing Forum (IDPF From the IDPF site: "'.epub' allows publishers to produce and send a single digital publication file through distribution and offers consumers interoperability between software/hardware for unencrypted reflowable digital books and other publications."
HTML HyperText Markup Language. Web pages are formatted with HTML. See also: XHTML.
linking service A company that indexes and helps clients maintain DOIs.
metadata Data that describes other data. For example, metadata can be placed in the header of an HTML or XML file, describing the file's contents and structure. Metadata is often formatted as XML, and there are metadata standards, such as Dublin Core.
Mobipocket A suite of tools for packaging and reading e-books. The file format generated by Mobipocket Creator is .prc. These files can also be read natively on the Kindle. However, Mobipocket Reader can display many common file formats.
namespace A standard specification that lists all of the rules governing tags, attributes, etc. The attribute xmlns is used to declare a namespace. It points to the URI of a file (usually on the web) that provides the specification. Assigning a namespace to an element (generally the root element, and therefore the whole document) allows a validation tool to accurately determine what syntax is allowed in the document markup.
ONIX An XML standard for the electronic exchange of book product metadata, maintained by EDItEUR (
open access A publishing model that provides full online access, free of charge, to the publication. Revenue to cover costs is provided by institutional support, grants, author fees, and other means. A list of open access journals is maintained here:
open source A software development model in which the source code for the software is posted online for anyone to analyze, test, and improve. Given a sufficiently active community of professional programmers, bugs and security problems are discovered and fixed more quickly than in proprietary software. Linux is an example of open source software.
OS Operating System. Examples are Windows XP, Mac OS X, Android, and Symbian OS. All devices have an OS, but some are less well known, or are unique to a particular device. Among mobile devices, Google's Android OS runs the Barnes and Noble Nook, the Motorola Droid, and many others. The OS on the iPhone is referred to as the "iPhone OS." The Kindle OS is actually a modified version of Linux.
parent An element that encloses the current element.
PDF Portable Document Format. Developed by Adobe, and formerly proprietary, PDF is now an open standared.
platform A software environment, usually proprietary, for providing a service or product such as e-books. Not to be confused with OS or ecosystem. For example, one can speak of the "Kindle platform" and thereby refer to all the software that displays kindle books, whether it is on the Kindle Reader, and iPod, or a PC. By contrast, the Kindle "ecosystem" would also include your personal account on and the arrangements Amazon has made with publishers.
processor An XML processor is a program that transforms XML into HTML, XML, or formatted output, such as PDF or postscript. Some common processors are Saxon, xsltproc, and Xalan. However, a program like <oXygen/> ( will let you choose which processor to use. Also, recent web browsers can perform some of the basic functions of a processor to convert XML to HTML, as long as they are given a stylesheet. InDesign also functions to some extent as an XML processor.
parameter entity An alias to a character entity. Character entities are short codes, but they can be difficult to remember. To make the text easier to read for a human, abbreviations are defined and then used in the document, such as "caret" instead of "&#x02041".
schema The successor to DTDs. Like DTDs, schemas describe the valid elements and their legal usage in a document. Schemas are written in XML, support namespaces, are more extensible and easier to use and transform than DTDs. For the purpose of discussing a workflow, schema and DTD are sometimes used interchangeably.
stylesheet A file that contains formatting instructions to be carried out a file that contains marked-up text. XML stylesheets may contain expressions in XSLT, XPath, and/or XSL-FO.
tag Tags are the basis of XML markup. An opening tag consists of a left angle bracket followed by a word with no spaces, followed by a right angle bracket: <tag>. A closing tag is exactly the same, except that the word inside the brackets is preceded by a right slash:</tag>. Tags surround content<tag>content</tag> to create an element. Tags are case-sensitive.
TEI A set of guidelines maintained by the Text Encoding Initiative ( for the encoding of machine readable texts. An overview of TEI can be found here:
template There are several types of templates in XML processing, both in the generic sense of an incomplete framework or starting point, and in very specific senses. For example, stylesheets may contain template directives, which are snippets of XSL that explain how to transform XML when a particular pattern is encountered.
validation All programs that use XML perform some type of validation. A common web browser can tell you if the XML is well-formed, that is, if opening and closing tags match and there are no illegal characters. Real validation checks that the XML in the document conforms to the DOCTYPE declared at the start of the document and that no undeclared namespaces are used. Validation is a key part of an XML workflow, which will include a validation step before and after any transformation of the document.
Unicode Intended to be the holy grail of character sets, covering thousands of characters and most language scripts. UTF-8 is a Unicode character set that is expected in XML unless otherwise specified. Often it is specified anyway for clarity.
URI A file location, expressed as a network path. The path is usually to a file on the Internet, but it may be to a shared local resource, such as an intranet fileserver, or even to a file on your hard drive. Stands for Uniform Resource Identifier.
XHTML Extensible HTML. Essentially the same as HTML, but it conforms to XML syntax. XHTML and HTML documents look very similar at first glance, but an XHTML document can be parsed by an XML processor, not just a web browser.
XML Very simply put, XML is a way of marking up all the text in a document so that it can be styled and transformed reliably by a computer program. It stands for eXtensible Markup Language. Just as with a spoken language, we use the term to refer to the whole language itself, as well as samples. So we say something is "in XML" or "that's XML" interchangeably. XML itself is not proprietary, is maintained by a standards organization, and is used in wide variety of data interchange.
XPath In stylesheets, XPath is the language used when specifying where a transformation should be applied. It describes a hierarchy of tags or elements.
XQuery A language for querying XML data.
XSL eXtensible Stylesheet Language. Actually a family of languages: XSLT, XSL-FO, XPath. A language for manipulating XML.
XSL-FO XSL Formatting Objects. A language for transforming XML documents into printable output, generally as PDFs.
XSLT eXstensible Stylesheet Language Transformations. XSLT specifies how to style XML text.