IMAP - Internet Message Access Protocol
Allows a client to access and manipulate electronic mail messages on a server.
IMAP4 permits manipulation of remote message folders, called "mailboxes", in a way that is functionally equivalent to local mailboxes.
IMAP4 also provides the capability for an off-line client to resynchronize with the server.
IMAP4 includes operations for creating, deleting, and renaming mailboxes; checking for new messages;permanently removing messages.