What is the difference between IMAP and POP email? It’s a good question and one of the most commonly asked ones I get from my website hosting clients.

Think of IMAP as being the keys to a remote computer where your email is stored. When you set up an email account on your computer or device using IMAP what you are doing is basically giving that app access to the mailbox that has been created for your email address on the mail server. You’re not downloading your email to your device, you’re just looking at what is in the mailbox on the server itself.

If you give the same IMAP details to several devices, such as your phone, desktop computer and tablet, all those devices will be able to look inside the mailbox on the server too and see the same messages. So for example, if I set up dallas@dallasdahms.net on all my devices as an IMAP account and you were to send me an email on that address, I could look at it from any of the devices at any time. I can also reply to it from any device and I can see the reply on any of my devices because I am actually giving remote reply instructions to my mail server so it saves the message there, not on my device.

If I delete an email on my iPhone it will also be deleted on my desktop computer that has been set up to use IMAP as well as any other devices where I am looking at it using the IMAP method. Basically it’s synchronized email and it’s very convenient to use wherever you go.

However, the downside to using IMAP is that eventually you are going to run out of disk space depending on how much space you allocated to your email account on the server. That brings me to an explanation of the POP method of setting up an email account.

When you create an email account and you set it up as a POP account on your device something different to IMAP occurs when you check your email. What happens is that your device logs into the mail server and downloads the message to your local device and stores it there. At the same time, depending on how you have your POP account set up in your email application you can either leave a copy of the message on the server, or you ask the program to delete it immediately or after a pre-defined amount of time. Obviously if you leave it undeleted on the server you will also eventually run out of storage space.

The upside to using POP email methods is that because you are storing messages on your own devices you would generally have a lot more storage space than you have on the server. The downside is that your email is not synced across devices, so if you reply to an email from your desktop computer, the only copy of it will be on that computer. If you lose your computer you also lose your email records.

I hope this has been helpful and if you have any questions about email you know you can always POP me one for further input. 🙂