The RTM specification defines an RDF vocabulary which describes how RDF triples are converted into Topic Maps constructs. While that approach certainly works and has its advantages (like embedding the mapping into the RDF source), people familiar with Topic Maps have to write the mapping in an RDF format and the mapping may become verbose. More importantly, it is not possible to reuse an existing mapping within another mapping.

CRTM provides the same expressiveness as RTM and offers some additional features like translating the optional language tag into scope and makes the reuse of mappings possible.

This language operates with the same algorithm as described by RTM; it’s just an alternative, compact syntax (aside from the enhancements which are not supported by RTM).