posting: n. Noun corresp. to v. post (but note that post
can be nouned). Distinguished from a `letter' or ordinary email
message by the fact that it is broadcast rather than point-to-point.
It is not clear whether messages sent to a small mailing list are
postings or email; perhaps the best dividing line is that if you
don't know the names of all the potential recipients, it is a
posting.