What is the IMAP Protocol?
The IMAP protocol is used for accessing email stored by the server instead of the client. Clients can store a cached copy of the email repository which can improve performance over slow network connections, as well as enable offline access to emails. For this to work, two-way synchronization is needed, and thankfully IMAP supports it! Along with offline access, the synchronization capabilities of IMAP enable users to access their email accounts from multiple machines, devices (such as a Blackberry or iPhone), or clients.
Since the "master copy" of an email account using the IMAP protocol is stored on a server, it is possible that the server was built using fault-tolerant methodologies. This has the added benefit of potentially reducing the likelihood of catastrophic data loss.
For these reasons and more, businesses often use the IMAP protocol for their email needs.
Webmail Clients
Webmail clients almost always use the IMAP protocol.
- SquirrelMail
- Roundcube
Clients Supporting the POP Protocol
- Outlook
- Outlook Express
- GMail
- Thunderbird