Overview
The Post Office Protocol Version 3 (POP3) is an application-layer internet standard protocol allowing users to retrieve email from a mail server. Designed for smaller nodes with limited resources, POP3 enables workstations to dynamically access and manage mail from a central maildrop. It operates by establishing a connection to the server, retrieving messages, and typically deleting them from the server after download, although options exist to leave mail on the server. POP3 is suitable for environments where extensive server-side mail manipulation isn't required. The protocol uses a simple command set and response format over TCP port 110. The protocol is defined by RFC 1939. The protocol supports authentication to ensure secure access to user mailboxes. It's widely used in email clients to provide a standardized way of retrieving email.