POP3 (Post Office Protocol) and IMAP (Internet Message Access Protocol) are two different email protocols. Both allow you to access your emails offline from your preferred email client.Both POP3 and IMAP4 has some functional difference.
POP3 vs. IMAP: Technology
* POP3 always downloads all new emails locally to your computer(by default, also can store the copy of emails in the server).
* IMAP downloads message summaries and doesn't download the entire message until you explicitly select it.
POP3 vs. IMAP: Email Inbox Display
* POP3 downloads all emails into 1 mail folder called "Inbox".
* IMAP preserves your folder structure in a main folder called "imap.domain.com".Using the IMAP protocol, all your mail stays on the server in multiple folders, some of which you have created. This enables you to connect to any computer and see all your mail and mail folders.
POP3 vs. IMAP: Multi-Computer Access
* POP3 is useful if you only access your email from one computer, since the email is typically downloaded locally (this is the default and can be changed).When you open your mailbox, new mail is moved from the host server and saved on your computer. If you want to be able to see your old mail messages, you have to go back to the computer where you last opened your mail.
* IMAP allows email to be manipulated from a desktop computer at home, a workstation at the office, and a notebook computer while traveling, without the need to transfer messages or files back and forth between these computers.
POP3 vs. IMAP: Email Storage
* With POP3, your emails can be automatically erased from the server after they are downloaded freeing up space in your account.
* IMAP keeps all emails on the server until you erase them.
POP3 vs. IMAP: Internet Connectivity
* In general, IMAP is great if you have a dedicated connection to the Internet or you like to check your mail from various locations.
* With this type of account you do not have to stay logged on to the Internet. You can log on when you want to receive and send new messages. Once your new messages have been downloaded to your computer you can log off to read them. This option is good when you connect with your modem to DAS and are charged for your connection or you have an older computer.