How is metadata used for indexing and searching in DITA outputs?

In DITA outputs, metadata plays a vital role in indexing and searching. It is critical for enhancing the indexing and searchability of content in generated outputs by employing metadata elements, keywords and index terms, custom metadata, searching and indexing tools, and content categorization.

  • Metadata Elements: DITA provides specific elements for embedding metadata within topics. Common metadata elements include <keyword>, <indexterm>, and <othermeta>. These elements allow content creators to associate relevant metadata with specific topics or elements within topics.
  • Keywords and Index Terms: <keyword> and <indexterm> elements enable the attachment of descriptive terms, keywords, or index terms to topics or sections of content. These terms serve as markers for search engines or indexing tools to recognize and associate with the content.
  • Custom Metadata: DITA permits the inclusion of custom metadata elements. Organizations can define additional metadata elements based on their specific needs, enhancing the precision of indexing and search.
  • Search and Indexing Tools: Search and indexing tools that process DITA outputs use embedded metadata to create searchable indexes. This enables users to find relevant content quickly.
  • Content Categorization: Metadata aids in categorizing content. For example, it can classify content by topic, audience, product version, or any other relevant criteria, which in turn helps users filter and locate the information they require.


A DITA-based product documentation set for a software application needs to be more searchable and discoverable. To accomplish this, metadata is added to the topics:

Metadata for Topics:

<keyword> elements are included within topics to specify relevant keywords related to the content. For a topic about “Advanced Settings,” keywords like “configuration,” “preferences,” and “advanced options” are added.

<othermeta> elements are used to define custom metadata such as “product version” or “operating system.”

Index Terms:

<indexterm> elements are placed within the text where significant concepts appear. For example, in a topic about “Troubleshooting,” <indexterm> elements are added to phrases like “error messages” or “common issues.”

By embedding this metadata, search engines and indexing tools can create an index of the content that includes these keywords and index terms. Users searching for terms like “advanced settings” or “error messages” can quickly find the relevant content. Furthermore, the custom metadata such as “product version” allows users to filter content based on specific criteria.