POP3 (Post Office Protocol version 3) is a mail protocol used by email clients to retrieve email from a mail server. It is commonly used for personal email accounts and allows users to download emails from the server to their device for offline access. Once emails are downloaded, they are typically deleted from the server, unless configured to keep a copy. POP3 service requires a username and password for authentication and uses TCP port 110 to communicate between the email client and server.
