Understandably there is a reasonable amount of confusion over the differences and advantages/disadvantages of POP vs IMAP for mail.
We are going to break up the debate over POP vs IMAP right here, right now. Here goes!
But first a little history lesson. POP mail was originally created as a result of the 1970’s creation of SMTP Reference Thus spawned POP in the early 1980’s. Thus a really old technology used primarily for one terminal download access. Reference. Latter aberrations of mail programs allowed for so so attempts at keeping the mail on the server. Assuming this did not fail due to a glitch, or an update, unchecking the “Leave copy of message on server” option, you could use POP on more then one computer, or device, and load them all up with tons of email, in tons of places.
Fast forward a few years to 1986 and IMAP was born! Reference. Given it took many revissions for it to get to IMAP4 which we use today, but IMAP brought to the table a few things POP just could not. Namingly the following: Only part of the message needed to be downloaded as the message resided on the server, not on the client(NO CONCERN OF A CLIENT BECOMING DOMINANT AND STEALING ALL YOUR MAIL, common with POP), connections on demand, mail folders not just an Inbox, and many more you get the point. Needless to say wipes the floor with POP.
So in the end basically it winds down to this:
POP’s Primary objectives in life(not withstanding what an email client may have for special options)
1. Downloads all mail to the computer it connects to. Unless that computer has special options to do otherwise.
2. Does not synchronize mail in any fashion.
3. Uses the highest bandwidth of the two formats due to it’s download basics. Unless mail program has special options.
4. Can have special settings OUTSIDE of specifications with mail programs to leave a copy on server, but is historically known to fail over time.
IMAP’s Primary objectives in life
1. Download ONLY headers till message is selected. Unless mail program has special options selected to do otherwise.
2. Does synchronize mail with devices with out modification. Is not plagued with POP’s client issue with one device stealing mail glitch.
3. Is more bandwidth friendly in most cases depending how the user has their mail client setup to check and receive mail.
4. Does need to have an active connection to the internet to read non-read messages in most cases. Client dependent option.
We hope this helps you sort out some of the debate over POP vs IMAP, and resolve some of the more heated arguments over which is better. As you can see they both have short comings, but POP, defiantly has the shortest of them all in today digital world. The lack of natural server side support for synchronization really kills it for most people as the client program is fully responsible for all routines of mail operation of mail delivery or if it even will make it. And as most of us know, client software is rarely up to spec.