QUOTE
can I switch to IMAP, try it, and go back to POP
Maybe/sort of. First, your provider would have to have both services available, or you'd have to have at least one POP provider and one IMAP.
But it's not going to be fully equal swap when/if you switch. The major difference between the two methods is:
POP is basically a one-way system.You request your mail, with any one device.
That device downloads it to only that one device.
The message is deleted from the service.
But it is stored on whatever device that downloaded/read it.
IMAP allows you to download/read the message one many different devicesAs many times as you want (until you delete it from the service)
And all your other devices can still read/download it until it finally gets deleted.
You may never actually store the message on your own device(s).
So, once you use POP to view your message, it won't be available to any other device (unless you send it to yourself, again). In other words, 'you can't go home, again.'
OTOH, what you read/download on an IMAP account will still be there if you decide to use POP. So, you could 'go home, again.' At least once for each message.
Back when we had only one device (like a 8MHz 16K RAM computer) POP was fine. Now, many have a computer, a smart phone and a laptop/iPad and want to have all their messages available on all devices, no matter which they might be using or where they might be on Earth or nearby it.
The above is quite simplified and generalized, of course. Some POP systems can have be set up to act similar to IMAP in some ways, and vice versa.