E-mail is the most common use of the Internet. Using e-mail a user can send text, picture, sound, programs or even movies to any other person on the Internet anywhere in the world. Each user on the Internet has a unique address in the format - user name@domain name. This address helps you in identifying a user to whom you wish to send e-mail. The main advantage of using e-mail is the speed at which delivery takes place. Second advantage is that it costs almost the same regardless of the distance.
How does E-mail Works? : The send e-mail to someone you need to know his email-address. You do not need to know the hardware and software specifications of the recipient.
• The sender composes the mail message using his mail client software. e.g. Netscape mail, Outlook Express, Eudora, Pine etc.
• When you send an e-mail message, the message is message is stored on a server until the recipient can retrieve it. Many mail servers use the post office protocol (POP). Nearly all ISPs and LANs maintain one or more mail servers. After composing the mail message the user sends it to the recipient's e-mail address. The message propagates across the Internet before it reaches the mail server of the recipient. The domain name identifies recipient's mail server and the user name identifies the recipient on that server.
• The recipient connects to his e-mail account on his mail server to read the message. For propagation of message across the internet, the e-mail handling system on the send's computer packages the message and prepares it for propagation. The messages are broken up into small pieces and put into envelopes called 'packets'. The packets are all addressed to the final destination. These packets are sent to the Routes of the network so that they can be forwarded. These packets are sent via cables or satellites as required and finally they reach the Router of destination network. The packets are received as assembled back on basis of packet numbers to get the final full message as it was sent.