Both IMAP and POP3 are protocols that allow you to receive emails from a remote server. Your email client uses these protocol to connect to your mailbox server. You may have your email client on your smartphone, laptop and desktop, and this is where IMAP and POP3 have different uses.
Post Office Protocol version 3 (POP3) downloads mail from the server and often deletes it from the server after it has done so. This means that depending on when your mail client checks for mail, you'll only receive the email on one device or mail client. This also means that when you delete an email from one device, it will not be deleted from another. For example, if you receive emails on your smartphone, deleting them won’t also delete them on your desktop mail client, so you will have an email that you have viewed appear as unread.
Since POP3 downloads emails from the server and saves them in a local storage area, losing or damaging your local storage may cause you to lose all of your emails.
Internet Message Access Protocol (IMAP) on the other hand, is suited for people who want to receive email on more than one device, which nowadays is most people who carry a smartphone. IMAP stores email on remote servers rather than downloading them to local storage, which is how the emails can be viewed on different devices. When you read, download or make any changes to emails on one device, it will synchronise across any other device using the same account. IMAP has the ability to only download the header of an email so it can be much quicker.
We recommend you use IMAP.
POP3 offers very few, if any benefits. When you are setting up your mail client, you will have the option to choose from IMAP or POP3. To set up either, you simply need to access your email account information through cpanel.yourdomain.com.