<messaging, protocol> (POP) A protocol designed to allow single-user computers to retrieve electronic mail from a POP server via TCP/IP. The default port is 110.
The POP server might be a computer with a permanent Internet connection whereas its clients might only connect to it occasionally, e.g. by modem.
There are (in 1994) three versions: POP, POP2, and POP3. Later versions are NOT compatible with earlier ones.
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Nearby terms: posting « postmaster « post office problem « Post Office Protocol » post-order traversal » POSTQUEL » PostScript