Glossary Updates12 new terms added to the glossaries · October 2, 2026, 22:44 CEST
AI TechDocKnowledge

Glossary · Specialization and domains

DITA specialization

Also known as: specialization, generalization, information type specialization

In DITA, specialization is the mechanism for defining new element types and attributes as extensions of existing ones. A specialized element is based on an existing element, declares its ancestry in the @class attribute and can always be processed, or generalized, as its ancestor.

  • DITA
  • Architecture

In one sentence

DITA specialization defines new element types based on existing ones; the @class attribute records the ancestry so processors can fall back.

Example

A company specializes <task> into <maintenanceTask>; its class attribute “- topic/topic task/task maintenanceTask/maintenanceTask ” lets a standard processor publish it as a task.

Explained in context

Context cards connect this term with others to answer one question. Also in British English and German.

How it applies

  • Technical documentation: Specialization lets an organization create its own document types — for example a “maintenance task” or an “API reference” — without leaving the standard. The new type inherits the processing of its base, so existing publishing pipelines keep working.
  • How it works: Each element carries a @class attribute listing its ancestry, such as - topic/topic task/task or - topic/body task/taskbody . Processors match on the class value, not the element name, so an unknown specialization is handled like its nearest known ancestor.
  • Kinds: Structural specialization creates new topic or map types (concept, task and bookmap are themselves specializations). Domain specialization adds elements or attributes that can be used across topic types.
  • Generalization: A specialized document can always be converted back to its base types, which makes content exchangeable between organizations with different specializations.
  • AI and retrieval: The @class attribute gives every element a machine-readable meaning. A model or a converter can recognize a custom <torqueValue> as a keyword or phrase by its class ancestry, even without knowing the specialization.

Specialization vs. constraint

Specialization creates new element types with new semantics. A constraint only restricts an existing content model and adds no new semantics.

In DITA markup

The class attribute of a task's body element, as supplied by the document type:

<taskbody class="- topic/body task/taskbody ">…</taskbody>