A message sent to a newsgroup or mailing list (may also be called "a post") or the act of sending it. Distinguished from a "letter" or ordinary electronic mail 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 e-mail; perhaps the best dividing line is that if you don't know the names of all the potential recipients, it is a posting.
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Nearby terms: postfix syntax « POSTGRES « PostgreSQL « posting » postmaster » post office problem » Post Office Protocol