For companies wanting to move to a topic-based structured authoring model the choice between standards can be bewildering. In the first of a series, DCL News looks at a typical scenario facing a publications manager.

In recent years, two distinct, yet comparable, approaches to topic-based authoring have developed and reached a level of prominence.

I'm sure many of you have heard the buzz around two standards, S1000D and DITA, that are being championed as the new approach to producing structured, or topic-based, technical information, but could be finding it confusing as to which one, if any, might apply to you. The aim of this article is to provide a broad overview and give some general guidance.

In recent years, two distinct, yet comparable, approaches to topic-based authoring have developed and reached a level of prominence.

• S1000D is an international standard that was initially developed in the aerospace industry and is now being applied to a large number of industries where large complex pieces of equipment or complex processes are produced and supported.
• The Darwin Information Typing Architecture (DITA) was developed in the computer industry and is often applied to intellectual property-driven products and processes.

What is Topic-Based Authoring? - Let's consider the case of the Technical Publications manager at Big Holes, Inc., a manufacturer of digging tools. He has been finding the costs of his traditional page-based manuals expensive to produce and revise, plus he is facing increasing demand from his customers to move to electronic delivery on either CDs or as part of the digging equipment trouble-shooting programs. By moving to a topic-based model he can write smaller "chunks" of information that can then be reused to produce both the traditional paper-based manuals as well as different types of electronic output his customers require. By keeping those "chunks" in a content management system he can easily track where the information is used, making revisions quicker and cheaper, or even use it to assemble brand new manuals with a minimum of rewriting. Having decided to go electronic, he must now decide which approach to use.

Fundamental to Big Holes, Inc.'s development path is Topic-Based Authoring. A Topic is a self-contained piece of information that guides the user through a particular process or set of actions. It has its own subject, its own beginning, middle and end.

Example of a self-contained Topic

TITLE:

About using the telephone's features

SHORT DESCRIPTION:

Your telephone has many features that allow you to handle calls in a variety of powerful ways.

BODY:

In this chapter, you will learn how to use the features of your phone. If you have any questions about these features, contact your systems administrator.

REFERENCE:

The features discussed in this chapter are automatic callback automatic preselect automatic speakerphone answer background music call forwarding call waiting

Writing self-contained topics is a change of style for most Technical Authors as it requires the discipline to avoid conditional references (such as "as we discussed earlier"), and to make sure that the topic can both be read as a standalone section as well as in the context of the surrounding topics. This is vitally important if the topic is to be read as part of a search result on a website or similar.

Why Use Topic-Based Authoring? - Breaking down documents into topics means that your information is in smaller chunks that can be reused in many places. For example, one standard Warning notice could be used across many topics, and across projects, in hundreds of places.

Breaking down documents into topics means that your information is in smaller chunks that can be reused in many places

With your documents broken down into small reusable chunks you can now use the same data in a variety of documents and outputs. This is what is meant by repurposing. Repurposing allows you to plan for a variety of delivery modes as well as uses. One piece of information can be used multiple times across a number of Maintenance Manual topics, as well as in Training Manuals, and perhaps in other types of material.

Authoring in a neutral standard such as the eXtensible Mark-up Language (XML) allows for this level of flexibility. As a result of its structured nested architecture, authoring in XML makes it cheaper to adopt a structured approach to authoring and building higher quality documentation. It allows best practices from your own, and other industries, to be adopted and ported into your own solutions. Using a neutral format allows for easier transport and sharing of self-contained information chunks between partners, vendors and customers.

S1000D vs. DITA - Both S1000D and DITA use the same underlying concepts and aims, yet approach Topic-Based Authoring in slightly different ways. In determining which approach would suit his needs best, the Technical Publications manager of Big Holes, Inc. needs to consider the pros and cons for each standard.

S1000D	DITA
Self-contained TASKS	Self-Contained TOPICS
Chunks of reusable information - "Data Modules"	Chunks of reusable information - "Topic Types"
Allows assembly of content and publishing in multiple ways using "Publishing Modules"	Allows assembly of content and publishing in multiple ways using "Topic Maps"
Specifies the use of a Common Source Data Base to manage the information chunks.	Recommends, but does not specify, the use of a Content Management System to manage the information chunks.

Both use ISO standards as their underlying technology, specifically both are XML-based implementations.

Given the various similarities, perhaps the best indication of which approach may be best for your particular circumstance is to consider their two different starting points. The development paths of the standards accounts for the differences in approach to what are essentially similar solutions. S1000D was originally developed from the need to support large and complex pieces of equipment in an efficient manner; DITA was driven by a publishing need to find a way to better manage and deliver what was becoming an "information glut."

As a consequence, the S1000D model is a more structured, defined approach that in some ways mirrors the physical structure of the equipment being supported, while DITA is a less formal approach that applies structure to a conceptual idea-based paradigm.

The development paths of the standards accounts for the differences in approach to what are essentially similar solutions

In summary it seems that S1000D suits long life cycle, structured projects where spare parts are involved, while DITA is better-suited to Intellectual Property-driven products, such as software and processes.

From the above it would seem that the best solution for Big Holes, Inc. would be to adopt the S1000D standard, as their digging machines have long service lives and regular maintenance cycles.

But S1000D is an Aerospace and Defense industry standard that includes a lot of industry-specific terminology; so how would a "civilian" company go about applying it to their environment? What changes need to be made to make it work for other industries, and how does this affect production and exchange of technical information? In a future issue of DCLNews we will look at the steps needed to adapt S1000D for use in a non-aerospace and defense environment.

DCLnews Editorial