The IMAP also known as the Internet Message Access Protocol is an Application Layer IP which permits an access to the e-mail on a remote email server to an e-mail client. The present version of the IMAP i.e. the IMAP version 4 revision 1 or the IMAP4rev1 is well-defined by RFC 3501. An IMAP server usually pays attention on the well-known port i.e. 143. IMAP and SSL together, known as the IMAPS, is allocated a well-known port figure 993.
IMAP maintains both off-line and on-line procedures. E-mail clients, who use IMAP, usually drop messages on the server till the user openly removes them. The feature of the IMAP process allows various clients to handle the same work in the same mailbox. Most e-mail clients maintain IMAP as an addition to the POP (Post Office Protocol) to recover the lost messages; nevertheless, fewer email facilities maintain IMAP as well. IMAP proposes admittance to the internal mail storage. Customers may pile native copies of the message communication, but these are just the measures to be a provisional cache