This directory used to host various material of the IVOA semantics WG.

This has now, for better or worse, all moved to github.  See:

https://github.com/ivoa-std/VEPs for version-controlled VEPs
https://github.com/ivoa-std/vocinfo for the standard

https://github.com/ivoa-std/Vocabularies for the vocabularies themselves
(which is mainly there for the vocabulary maintainers)