Post Office Protocol (POP) and the Internet Message Access Protocol (IMAP) are specifically designed for use by individual users retrieving messages and managing mail boxes.
SMTP is a delivery protocol only. In normal use, mail is "pushed" to a destination mail server
| POP3 | Post Office Protocol 3 ( download emails ) |
|---|---|
| POP works by contacting your email service and downloading all of your new messages from it | |
| IMAP | Internet Message Access Protocol ( read emails ) https://en.wikipedia.org/wiki/Internet_Message_Access_Protocol |
you aren't actually downloading or storing it on your computer; instead, you're reading it from the email service. IMAP only downloads a message when you click on it, and attachments aren't automatically downloaded. This way you're able to check your messages a lot more quickly than POP. | |
Client Commands Server Response | |
| SMTP | Simple Mail Transfer Protocol |
| SMTP is a delivery protocol only. In normal use, mail is "pushed" to a destination mail server | |
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