Post Office Protocol (POP)
WebDynamic™ Web Glossary
The way many email programs retrieve messages from a mail server. Email is delivered on the Internet to the mail server, and an email program running on a personal computer retrieves that email through POP.
Unlike SMTP, which is used primarily to transfer mail messages between mail servers, POP provides a way for mail programs to interact with virtual mailboxes in which messages wait until they are sent or retrieved.