Source : Free On-Line Dictionary of Computing

Great Renaming
     
         The {flag day} in 1986 on which all of the
        non-local groups on the {Usenet} had their names changed from
        the net.- format to the current multiple-hierarchies scheme.
        Used especially in discussing the history of newsgroup names.
        "The oldest sources group is comp.sources.misc; before the
        Great Renaming, it was net.sources."
     
        {FAQ (http://www.vrx.net/usenet/history/rename.html)}.
     
        [{Jargon File}]
     
        (2000-07-14)