The Post Office Protocol is an application-level protocol within an intranet which are used by the local e-mail clients to send and retrieve e-mails from a remote server those are connected using TCP/IP. POP is one of the most prevalent protocol fro the usage of e-mail. The POP and its procedures support the end-users with dial-up network connections.

POP allows the users to retrieve e-mail when connected and later allows viewing and altering the retrieved messages. This is done with a promising feature – without staying connected. The process of using emails over POP is to connect, retrieve the messages, and store them on the user’s PC as a new message. Later these messages can be ‘deleted from the server’ and disconnecting the server – makes POP a distinguished protocol.