What is the difference between POP3 and IMAP?
Find out the difference between IMAP and POP3 protocols used when connecting to an email inbox and the implicit operational impact.
IMAP and POP3 are the connection protocols used by the majority of email clients.
The effective difference between the two is the final location where the emails will be stored.
In the case of using IMAP, emails will be stored on the Server.
On the device accessing the mailbox, only a list of messages and copies (cache) of these will be downloaded when they are viewed.
Thus, for POP3, the first device accessing the mailbox will download all emails locally, and the emails on the server will be deleted.
Emails will only be accessible locally, for that device that accessed the mailbox in question.
The same situation will occur upon receiving new messages.
Consequently:
IMAP is recommended for mailboxes that will be accessed by multiple devices and/or different people.
POP3 is used in environments where storage limits are a major consideration, and local storage of emails is a reliable option.
An important mention, certain applications / email clients offer the option to save a copy of messages on the server when using POP3.
It is recommended to check in advance if the chosen application supports this functionality.