E-mail Internet Applications

SMTP - SMTP is an abbreviation for Simple Mail Transfer Protocol, it is an internet standard for the sending of electronic mails(E-mails) across IP networks. Websites that provide this kind of services would be for example: hotmail.com, gmail.com, yahoo.com. These servers use SMTP to send and receive mail messages on behalf of the users.

POP3 - POP3 is an abbreviation for Post Office Protocol, version 3. It is an application layer internet standard protocol allowing the user to retrieve download mail from a remote server using a TCP/IP connection, it deletes all mails from the server after the user disconnects from it.

IMAP4 - IMAP4 is an abbreviation for Internet Message Access Protocol. It has the same functions as POP3, but it can also support both on-line and off-line modes of operation, it also allows the function of storing mail in the server, however, it requires a better CPU and larger hard disk space because of the potential amount of information that is going to be stored.