Glossary · Specialization and domains

DITA domain

Also known as: domain specialization, domain module

In DITA, a domain is a set of specialized elements or attributes for a particular subject area, such as software, user interfaces or hazard statements, that can be added to any document type. Document types declare the domains they include in the @domains attribute.

DITA
Architecture

In one sentence

A DITA domain is a set of specialized elements or attributes for a subject area — software, UI, hazard statements — usable in any topic type.

Example

The user interface domain adds <uicontrol> and <menucascade>, so a step can mark up “Settings > Filter” as a menu path.

How it applies

Technical documentation: Domains provide vocabulary for a subject area that can be used in any topic type: the software domain (<filepath>, <cmdname>), the user interface domain (<uicontrol>, <menucascade>), the programming domain, the hazard statement domain and, new in DITA 1.3, the markup, XML mention, release management, MathML, SVG and equation domains.
Attribute domains: Domains can also specialize attributes from @props or @base. The @deliveryTarget attribute, new in DITA 1.3, is defined as an attribute domain.
Declaration: A document type declares its domains in the @domains attribute, for example (topic hi-d) for the highlighting domain; domain elements carry a class value starting with +.
AI and retrieval: Domain elements mark up meaning inline — a <uicontrol> is a button label, a <filepath> a path. That markup can be preserved as entities when content is chunked for retrieval.

Domain vs. structural specialization

A structural specialization creates a new topic or map type. A domain adds elements that can be mixed into many topic types.

In DITA markup

<step>
  <cmd>Click <menucascade><uicontrol>Settings</uicontrol><uicontrol>Filter</uicontrol></menucascade>.</cmd>
</step>