0001: Call the unit a topic

Decision: the unit this repository defines is called a topic, the word of DITA and of topic-based authoring.

Status: accepted, 2026-10-29. Shape: decision record.

Context

• The repository was opened as recursive-atom, and its unit was called a node: both were our words, chosen before the review asked what the field calls the thing.
• The frames of the three reviews answered. Practice and DITA say topic, with derivation called specialization; markup research says content object (OHCO); studies of trees on screen say node.

Decision

• The unit is a topic; the repository is reader-ergonomics-topic, in the family's naming scheme.
• The reviews take the field's names: information-typing, progressive-disclosure, document-model.
• "Node" stays where it is the field's own word: a node of a tree on screen, or of a markup model.

Consequences

• A reader from technical writing recognises the unit; GitHub redirects the old repository address, but not the old site.
• "Topic" had also meant a review subject in the evidence files; those uses now say review, so the word keeps one meaning.
• Risk: a reader may assume DITA's rules, which are not all ours. The topic's own rules are in shapes/topic.md.

See also

Decisions; the names each field uses, in the information-typing frame.