IMAP

    Internet Message Access Protocol

    A protocol for email retrieval and storage developed by Mark Crispin in 1986

    Alternative to POP(post office protocol)
    Application layer protocol - allows an email client to access email on a remote mail server
    Port 143
    Supports both online and offline modes of operation

    Advantages over POP:
          Connected and disconnected modes of operation
            Multiple clients simultaneously connected to the same mail box
              Access to MIME messaging parts and partial fetch
                Messages state information
                  Multiple mailboxes on the server
                    Server-side searches
                      
                  Built-in extension mechanism

                  Disadvantages:
                        Criticised for being insufficiently strict and allowing behaviours that effectively negate its usefulness

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