OSM mailing list as a forum
(the short link to the OSM mailing list in forum style: https://www.openstreetmap.at/talk )
The oldest form of communication in OpenStreetMap is the mailing list. Put simply, mailing lists are email distribution lists that forward an email they receive to all others who have also subscribed to the mailing list. This means that everyone on the mailing list receives all emails addressed to that mailing list. This allows discussions to be held and each subscriber to the mailing list receives all messages as emails and can store them personally if desired.