There are two ways that you can access emails.
POP3 (Post Office Protocol 3) is the traditional delivery method which has been used for many years. Messages are delivered to your web mail server, when your selected device program (typically Outlook) on your PC/Mac/laptop requests a download (send/receive action) the message is delivered to your in-box. You therefore have the entire message (and attachments) sitting on your PC/Mac/laptop so you can archive/reply/forward/delete – in other words it is up to you what you do with it.
Advance settings in most email programs will also allow you to keep a copy of the message on the server but if this is not pre-set the message is automatically deleted from the server when delivered. By keeping a copy of your messages on the server other PC/Mac/laptops/mobile devices can also receive the messages.
The other method of email delivery is IMAP (Interactive Mail Access Protocol). IMAP mail is delivered to the server in the same way as POP3 and then you connect to the server to see your mail. The mail is NOT stored on your local device but remains on the server.
IMAP allows you to access your mail from different devices, usually mobile phones hence its increased popularity. When the message is delivered using IMAP only the header (title/sender info) is visible, when you then click on the email it delivers the content but leaves a copy on the server.
You do not require an internet connection to view your downloaded emails
emails are not saved on the server (unless you activate the advance settings to save a copy) therefore not so likely to be lost should the server crash
server disk usage is minimal
available from any machine you use to access from (account/password required)
messages are stored on the server, so your email cannot be deleted/destroyed if your computer should crash, be stolen, or destroyed
Not available to other devices (unless advance settings are actioned)
Requires 3rd party applications for delivery (ie: Outlook)
You are relying on a 3rd party to archive your messages
Server space is limited
Servers holding your messages are not backed up
You require an internet connection to view your emails
Emails can be deleted if you stop paying the hosting fee
I recently went to Orlando. Before I left I emailed important info to my Android phone (IMAP), when I arrived they had been deleted, when I got back they reloaded!
Last year we lost our broadband connection for 4 weeks but I could continue to work because I had all my email instruction/messages on my local PC (POP3). During this time I had to use a 3G link and had a data download cap. Had I been using IMAP the costs would have increased.
POP3 is great for single, non-mobile devices but you need a 3rd party program to take delivery of your messages, or access to web mail (server). POP3 messages are also delivered in full to your device therefore you have more control over their archive and security
IMAP is the method of choice for mobile devices and multi-users but offers less control over message archiving and security. It also causes issues with high volume users because messages are stored on the mail server which can run out of space, or you could be charged for additional space.
Note: if you use a mobile device only for emails make sure you…
Delete old messages from the server
Use a static device (laptop, PC, Mac) to also store and back-up your messages
We do not back up our mail servers therefore the responsibility for archiving emails is with the client/user.