Domino System Administration

IMAP Mail Versus POP Mail

IMAP and POP mail were developed to serve different purposes. POP mail was intended to enable mail users to work offline. A POP mail client downloads messages from a POP mail server, then typically (though optionally) deletes the copies on the server. In the end, the only copies of the messages reside on the client computer. In a sense, a POP mail server used in this way is just a relay host—a place to hold mail temporarily until the user can pick it up.

IMAP, on the other hand, provides users the capability to work with their mail from more than one computer. Because the primary copy of every IMAP mail message is maintained on the IMAP server, even if one downloads copies to an IMAP client, users can work with ...