The Post Office Protocol, v3 (POP3) permits a workstation to dynamically access a maildrop on a server host. The POP3 protocol is used to allow a workstation to retrieve mail that the server is holding for it.

The RFC for POP3 is stored by the Internet Engineering Task Force (IETF).

For information on POP3, see RFC 1939: Post Office Protocol - Version 3.

For Microsoft licensing information, see Published Protocols and Royalty-Free License on Microsoft Developer Network (MSDN).