SDD Part 0: Introduction and Primer to the SDD Standard

4.7 Descriptive terminology.

The descriptive terminology element in SDD contains entries for a number of loosely related groups placed in three subsidiary elements; <DescriptiveConcepts>, <Characters> and <CharacterTrees>.

SDD <DescriptiveConcepts> express basic terminological concepts of a more general concept than "characters" (structural hierarchy, property hierarchy, methods).

<Characters> and their states are fundamental elements used in SDD to describe a taxon, specimen or other entity.

<CharacterTrees> define operational hierarchies for listing characters in a character definition report, in interactive keys, or in natural language reports