Pop3s
POP3 (port 110) or POP3s (port 995) stands for The Post Office Protocol. It’s an Internet standard protocol used by local email software clients to retrieve emails from a remote mail server over a TCP/IP connection.
Email servers hosted by Internet service providers also use POP3 to receive and hold emails intended for their subscribers. Periodically, these subscribers will use email client software to check their mailbox on the remote server and download any emails addressed to them.
Once the email client has downloaded the emails, they are usually deleted from the server, although some email clients allow users to specify that mails be copied or saved on the server for a period of time.
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