The DITA 1.3 learning and training support includes new domains that deprecate the DITA 1.2 interactions but provide a path for backward compatibility.
The DITA 1.3 domains include the following changes:
@id
attribute for interactions optionalIf you are implementing learning and training support in DITA for the first time, use the learningDomain2 domain for document types that need assessments.
If you have already implemented learning and training support with DITA 1.2 and none of the limitations adversely affected your support, then you can continue to use the learningDomain in document types that need assessments.