A big benefit of DITA is single-sourcing.
If you publish to multiple formats (web, online help, print, and so on), you can use the same set of DITA files for each piece of content. And that means that one set of files for multiple formats can be stored in one repository. You don’t have to worry about making the same updates in multiple file sets. Single-sourcing strengthens the way you create, develop and maintain content.
Single-sourcing also allows for another key feature of DITA–reuse. With DITA, you can reuse documentation that was created for one document in another document. For example, you could use a topic in training courseware, in a user guide, and in marketing information.
You can reuse a whole topic or part of a topic.
To reuse a topic, you would simply include the same topicref in a new ditamap. To reuse a part of a topic, you would assign an ID to the portion you want to reuse, and then use a conref attribute in the new topic to incorporate that portion.
This allows for consistent use of terminology, instructions, and concepts. And what happens when you have consistent information? Your customer gains confidence in your documentation and your product.