What is the pop3 server used for?

pop3 server is used to receive mail. pop3 is the third version of the electronic post office transfer protocol, which stipulates the protocol for personal computers to connect to the mail server of the Internet and download e-mails; and the POP3 server is a receiving mail server that follows the POP3 protocol and is used to receive e-mails.

The operating environment of this tutorial: Windows 7 system, Dell G3 computer.

pop3 server is used to receive mail.

POP is the abbreviation of Post Office Protocol. It is an electronic post office transmission protocol, and POP3 is its third version. It specifies how to connect a personal computer to the Internet's mail server and Download the electronic agreement via email. It was the first offline protocol standard for Internet email.

POP protocol supports "offline" email processing. The specific process is: the email is sent to the server, the email client calls the email client program to connect to the server, and downloads all unread emails. This offline access mode is a store and forward service that sends emails from the email server to a personal terminal machine, usually a PC or MAC. Once the email is sent to the PC or MAC, the email on the mail server will be deleted. However, most POP3 mail servers can "only download mails and not delete them on the server side", which is an improved POP3 protocol.

To put it simply, POP3 is a simple and practical email information transmission protocol, so the POP3 server is a receiving email server that follows the POP protocol. Different email service providers have corresponding POP server addresses, and this address will It is provided to everyone so that they can use it when using professional email management software such as Foxmail and Outlook.

Note:

POP is suitable for the offline model of C/S structure. The offline model cannot operate online, unlike IMAP4 (netscape supports IMAP4). When the client connects to the server and queries for new emails, all emails specified by the client to be downloaded will be downloaded to the client by the program. Once downloaded, the email client can delete or modify any message without further interaction with the email server. The POP3 client sends a command to the POP3 server and waits for a response. The POP3 command takes the form of a command line and is expressed in ASCII code.

The server response is composed of a single command line, or multiple command lines. The first line of the response uses ASCII text OK or -ERR to indicate whether the corresponding operation status is success or failure. There are three types in the POP3 protocol. status, approval status, processing status, and update status.

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