What is the SMTP protocol?
What exactly is the SMTP protocol?
SMTP stands for Simple Mail Transfer Protocol. Where IMAP and POP3 bring your mail in, SMTP takes care of sending it. Every time you click "send", your program uses SMTP to get the message on its way.
Explanation
You can think of SMTP as the postal carrier for your email: it delivers messages from one server to the next until they land in the right mailbox. That's how the SMTP protocol works in practice. To send, you enter an outgoing server and port in your mail program. At Mailflux that's webmail.mailflux.eu, with an encrypted connection so your mail is protected on its way.
Example
You send a quote from you@yourbusiness.be to a client. Your program connects to the outgoing server via SMTP, which passes the message along until it arrives in your client's mailbox. To you it feels like a single click on send.
Where do you encounter SMTP?
You come across SMTP when you set up a mail program: alongside the settings for incoming mail (IMAP or POP3) you enter an outgoing server, usually with a port number and an encrypted connection. If that SMTP setting is wrong, you can receive mail but not send anything. At Mailflux the correct details are ready for you, and with automatic configuration you often don't even need to type them in yourself.
Related terms
Want to better understand how outgoing mail works? Read What is SMTP and how does outgoing email work?. There we go a step deeper.