Mail Access Protocols
The e mail message are usually sent to an email server that stores received message in the recipient e mail mailbox. The user retrieves message with either a web browser or an e mail client that uses one of a number of mail retrieval protocols.
Some clients and servers preferentially use vendor specific proprietary protocols. But most support the internet protocols, SMTP for sending e mail and POP3 ( post office protocols version 3) and IMP4 ( internet Mail Access protocols , version 4 for retrieving email allowing mterprebability with other servers and clients. SMTP can also be used for retrieving email. It is more suitable for permanent internet connection than say a dialup connection and is not supported by most e mail client software.