Description

   The LISTS command returns an index describing the mailing lists
   that the mail server handles. This description might not give
   the names of each and every available mailing list; for such
   information use the DIRECTORY/LIST command. The index is, more
   often than not, a simple description of the mailing lists handled
   by the server. It might also describe any policies associated
   with the lists (e.g., who can subscribe, how to post to the list,
   etc.).