Technicalities - the online newsletter for STC RMC

February /March 2004

Volume 44, Number 4

.pdf version

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XML fundamentals for technical communicators

by Betty Faulkner
Reprinted with permission from Sound Off!, newsletter of the Puget Sound Chapter of the STC.

The new Professional Development series kicked off on November 15 with an XML training seminar by Richard Lander, a program manager in the Common Language Runtime group at Microsoft. Lander has been active in the XML field for many years and has developed many of the schemas used at Microsoft. After starting with a detailed description of what XML is (and isn’t), Lander focused on the advantages of implementing XML in the documentation process.

XML is whatever you want it to be

Using detailed slides and code examples, Lander defined XML (Extensible Markup Language) and how it works. Although XML is a markup language like HTML, tags are defined by the user. This means that an XML content file must be described and interpreted by another file (a DTD or schema; see table below). Then the content file can be formatted for different output targets by using different style sheets (XSLTs).

Name	File	Description
XML	.xml	An “instance file” containing the content.
DTD	.dtd	An interpretation file that defines the document structure.
XML Schema	.xsl	An XML-based alternative to DTD.
XSLT	.xslt	A style sheet for transforming the instance file into HTML, print, etc.

Thus, XML is really a family of languages based on the XML syntax. Other languages include XPath (a syntax used in XSLTs), XForms (for creating Web forms), and XLink (allows XML elements to be linked so that content can be reused).

Because XML is not a programming language, third-party applications are required to handle XML files and transformations. The list below includes software recommended by Rich Lander and by class participants.

XML Editors:

XSLT Processors:

The benefits of authoring in XML

Lander next described how XML authoring supports specific documentation goals. XML provides reusability, an important feature for document sets with large amounts of duplicate content. When multiple individuals are authoring or reusing content, using XML guarantees a consistent structure, and managing XML content with an application such as Visual SourceSafe® ensures source control.

XML output is consistent and flexible (just add an additional XSLT for an additional output). XML can deliver highly customized content on demand using data-describing elements and metadata to enable complex filtering and searching.

Implementation strategies

Lander concluded the seminar with recommendations for successfully implementing XML technology into the documentation process. A DTD or schema must be chosen based on a well-defined content model. Will the DTD or schema have a strict or loose format; a content-based or format-based style? Other considerations include the types and requirements of deliverables and adequate in-house technical support. Finally, writers and editors must learn to use XML tools and embrace a new way of writing.

Resources:

Web sites

Generally Markup, Rich Lander’s site
Microsoft XML tutorial
Free XML tutorials from W3 Schools
CinCom TIGER XML tutorial, a Sun™ One Studio product
XML Introduction
Free XML tools and software

Books

(recommended by Rich Lander)

Kay, Michael. XSLT: Programmer’s Reference. Second edition. Chicago: Wrox Press, Inc., 2001. (Very advanced; one step above the XSLT specification.)
Walmsley, Priscilla. Definitive XML Schema. New Jersey: Prentice Hall, 2001.

Other books

(thanks to Diane Boos)

Daum, Berthold and Udo Merten. System Architecture with XML. San Francisco, CA: Morgan Kaufmann Publishers, 2002. (For advanced XML users. Explains using XML in system architecture. Requires an understanding of both system architecture and XML.)
Harold, Elliotte Rusty and W. Scott Means. XML in a Nutshell. 2nd ed. O'Reilly & Associates, Inc., 2002. (Intermediate users. Good as reference beyond the basics.)
Harold, Elliotte Rusty. XML Bible. 2nd ed. New York: Wiley, John & Sons, Inc., 2001. (Intermediate to advanced. Great reference but somewhat difficult for beginners.)
Holzner, Steven. XML Complete. New York: McGraw-Hill, 1997. (For beginners. Has a CD and code samples. More advanced than Visual Blueprint.)
Vander Veer, Emily A. and Rev Mengle. XML: Your Visual Blueprint for Building Expert Web Pages. Foster City, CA: IDG Books Worldwide, Inc., 2000. (For beginners. Gives code samples and explains where to use it very briefly in a two-page format.)

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