If you have a computer failure, and don’t have backups, that mail will be lost with no way to recover it.  The “On My Mac” or “On My Computer” refer to folders / mailboxes that have been created on your local computer and stored there.  If you have an IMAP connection, you can place folders on the server and organize your mail on the server. So, in Apple Mail, you will see the Server name, and the “Inbox”. Has a larger “disk storage” requirement than POP3.More complex then POP, and slightly slower, depending on the mail application used.Your mail is stored on the server, but most email packages cache the mail locally to help reduce any lag…  As well as granting off-line access to your mail.Folders can be created, and stored on the server, allowing all applications to access those mail messages.More robust, and you can have multiple email programs using the same email account simulateously.Supported by almost all major email packages.Tracks the state of your email, and your mail clients can use this information to keep themselves all in sync. You also can have folders that are on the server so you can organize your email, and depending on the installation IMAP supports server based searches.  Anything you delete from your work computer, will also be deleted from your home computer. Simply stated if you check your mail from home, when you get to work, your work mail will be read as well.  So IMAP allows the server to track if a message has been read, deleted, forwarded, etc, so that all IMAP clients are aware of this.  For example, the major issue with pop is that you are unable to share basic information between different mail applications. IMAP, or “Internet Message Access Protocol”, was designed in 1988 to fill in gaps that Pop created. Does not support folder access on the Server (all folders are local to your machine).
Your Mail is stored locally, so you can not share mail between mail clients, without duplicating each mail message.Supported by just about every mail package on the market due to it’s age.Your Mail is stored locally so the server does not have to have much storage or processing power, excellent for old hardware. The core issue with POP is it is designed to remove your mail  from the server and it is only stored on your local machine. POP, or Post Office Protocol is an older standard from 1984. There are three different major ways to handle email:  The little “On My Mac” label in Apple Mail, or Entourage’s “On My Computer” label…Īlmost every modern mail package offers a similar feature, but many people don’t understand what this means…  So here’s the scoop.