newsgroup: [USENET] n. One of {USENET}'s huge collection of topic groups or {fora}.

:newsgroup: [USENET] n. One of {USENET}'s huge collection of
topic groups or {fora}. Usenet groups can be `unmoderated'
(anyone can post) or `moderated' (submissions are automatically
directed to a moderator, who edits or filters and then posts the
results). Some newsgroups have parallel {mailing list}s for
Internet people with no netnews access, with postings to the group
automatically propagated to the list and vice versa. Some
moderated groups (especially those which are actually gatewayed
Internet mailing lists) are distributed as `digests', with groups
of postings periodically collected into a single large posting with
an index.

Among the best-known are comp.lang.c (the C-language forum),
comp.arch (on computer architectures), comp.unix.wizards
(for UNIX wizards), rec.arts.sf-lovers (for science-fiction
fans), and talk.politics.misc (miscellaneous political
discussions and {flamage}).
-- The AI Hackers Dictionary