I recently set up email on my new MacBookPro.  For the first time, I’ve set up every email account I have on a common machine.  I also made the switch from using POP email boxes to IMAP email boxes.  Some people have asked me what the difference is, so today, I’m going to talk a little about the differences and when you might want to use each kind.

What do the acronyms stand for?  POP stands for Post Office Protocol.  IMAP stands for Internet Message Access Protocol.

Think of how you deal with the post office, they deliver your mail to a single place — like Post Office Protocol.  Some mail programs will allow you to leave the mail on the server as well as delivering it to your inbox on your computer.  For the longest time, I used my Mac Mini as the main repository.   I might have some of the mail on my laptop, but once it downloaded to the Mini, I deleted it from the server.  This was, shall I say tedious. It’s a good system when you work with just a single computer.

IMAP stores mail on the server and keeps a matching copy on whatever computer you have it set up on.  This is ideal if you’re working from multiple computers, like I’ve been doing for years.  I didn’t really know what IMAP was or why I would want to use it until someone mentioned to me about a month ago that everyone is using IMAP now for accessing mail on multiple computers.  I asked for more information, and I thought, “Wow, that’s just what I’m looking for.”

I’ve done a little experimenting, but it seems, for me, the best settings are to store Junk mail and Trash on the server and have them automatically deleted after a specified period of time.  For me, I’ve set Junk mail to one week and Trash to one month.  I may adjust that last one to one week as well.  For now, this is important because Max OS X Mail is doing a terrible job of identifying SPAM accurately, so a fair amount of legitimate mail goes to the SPAM boxes.

So, the rule of thumb when deciding if you want POP or IMAP comes down to how many computers are you accessing your email from?  One or many.  If it’s a single computer, then POP is probably a good choice. Sometimes your provider only offers POP, then you have no choice — in my case, Earthlink only offers POP.  If you use multiple computers, IMAP is going to give you a more satisfying email experience, because your mail won’t be stuck on “your other machine.”