I am right now in the process of switching over to using an IMAP server to house all my mails and mailboxes. I am, however, trying to get a handle on the paradigm of how mails are handled within IMAP. Or, to be more specific, what is done with old Read mails.

In my old system, which involves MBOX-format mailboxes, there could be, say, the users Tom, Dick, and Harry. Each of them would have three mailbox files.

Tom, for instance, would have the MBOX files tom, tom.sent and tom.received. The new messages would be held in the tom file, and when he sends out a message, it gets stored in tom.sent. When he goes to exit from reading messages, the mailreader, in this case Elm, asks him:

Move read messages to "received" folder? (y/n)
If he enters "n" (or just hits <enter>) it keeps the Read messages in the tom box, if he enters "y" here, it moves all the Read messages over to the tom.received file, where they are now out of site, out of mind, but can still be gotten to if needed...

Now, as I said, I am moving over to an IMAP machine, and am going to convert my entire set of new (blahblah) and archived (blahblah.received) mails over to the new system, into their respective blahblah maildirs.

The trouble is, there doesn't seem to be anything equivalent to a blahblah.received folder in IMAP. I see Inbox, Sent, Draft, and Trash, and sometimes other folders. but nothing that seems to equate to Received.

Just how does IMAP deal with older, Read messages? Do they stay in the main Inbox (or maybe Cur[rent] box) indefinately, but then get "ignored" by the listing (i.e., it declares them "below the threshhold" to be shown, by, say, showing mails newer than a week old, but still shows them if you enlarge the threshold?) until told otherwise?

Is there a commonly agreed upon procedure (for want of a better word) used by IMAP users for moving, say, Last Months Messages into some kind of local, but still easily searchable, subdir?

Would I be better off moving all the blahblah and blahblah.received mails into the regular Inbox, or would I be better off keeping them in seperate subdirs from each other?

Bear in mind, I've got mails going back more than a decade, but I intend them to all be moved onto the IMAP machine.