What is a POP3?

This protocol is intended for receiving messages. It provides a simple way to access mail.

This protocol allows the user to download all messages to his / her device and then read them, with the possibility of permanently deleting them from the server.

POP3 protocol keeps messages temporarily until the owner comes to receive them, and allowing leaving a copy on the server or deleted it from the server once you receive the mail.

What is pop3 ?