Post Office Protocol (POP)
Definition - What does Post Office Protocol (POP) mean?
POP is an application layer protocol in the OSI model that provides end users the ability to fetch and receive email.
Techopedia explains Post Office Protocol (POP)
POP uses the TCP/IP protocol stack for network connection and works with Simple Mail Transfer Protocol (SMTP) for end-to-end email communication, where POP pulls messages and SMTP pushes them to the server. As of 2012, Post Office Protocol is in its third version known as POP 3 and is commonly used in most email client/server communication architecture.