Undoubtedly, you've heard about the benefits of managing your data with XML: data will be reusable across multiple applications, tools that understand XML will make your life easier, content producers and presentation specialists will be able to work independently, and so on. Does this really work, or is it just hype?

To answer this question, I introduce an exciting XML technology -- DocBook, a widely adopted DTD for technical documentation. Started in 1991 as an SGML application, DocBook is a mature markup standard used throughout the technical publishing industry. Now DocBook is available as an XML application as well.

DocBook is a large (> 300 elements) standardized DTD available as SGML or XML. It allows people creating technical documentation to focus on various elements' meaning, instead of the elements' presentation on the page. DocBook contains a comprehensive vocabulary and structure for representing concepts in technical publishing. It has elements for books, articles, and reference pages; structural markup like sections, chapters, appendices, and so on; and specific tags for source code samples and technical diagrams. The benefits of representing technical documentation with DocBook include:

• Content reuse in multiple formats -- Since DocBook documentation represents the document's structure, rather than how that structure displays, it can be published in multiple formats. A DocBook document can be converted to HTML, PDF, or any other presentation. It makes an excellent choice for context-sensitive help.
• Automatic reference generation -- A DocBook document directly indicates all of its chapters, sections, and graphics headings with markup. Stylesheets can automatically generate a table of contents, an index, lists of graphics, glossaries, and other forms of the document's cross-reference. Since these references are generated, changing a DocBook's source document (changing a heading, for example) automatically updates the next time the reference page is generated.
• Standardized stylesheets -- Organizations can develop DocBook stylesheets to unify the "look and feel" of their documentation. Groups of writers in separate organizations can collaborate on a single document to publish a document with a consistent visual style. Many freely available stylesheets also exist.
• Tools. A general agreement on what DocBook elements mean has resulted in a large set of available tools to manipulate DocBook documents. Adobe provides a set of DocBook tools for FrameMaker, for example. These tools make documentation providers and maintainers much more productive, and much of the DocBook formatting software is free.

The following example gives you an idea of what a DocBook document might look like:

<article>
<articleinfo> <title> DocBook - A DTD for Technical Documentation </title> <author> <firstname>Mark</firstname> <surname>Johnson</surname> </author> <copyright> <year>2001</year> <holder>elucify technical communications</holder> </copyright> </articleinfo> <para>You've undoubtedly heard...</para> ... </article>

Look familiar?

Earlier, I asked if claims about DocBook's benefits are just hype. Those using DocBook clearly answer, "no". Here are some of the places using DocBook today:

• Hewlett-Packard's 90 megabytes of HP-UX documentation;
• Red Hat's Linux documentation;
• KDE and GNOME's Linux desktop programs;
• Sun Microsystems's Solaris documentation;
• Novell's Netware documentation.

These examples clearly illustrate the high profile, industrial-strength usages of DocBook. If you're producing technical documentation, then you need to know about DocBook. Even if you aren't, DocBook demonstrates why XML is becoming so widely adopted --because it works.