How Email Servers Work:
There are many different types of email clients in use on the internet, such as Outlook, and Outlook Express, but most email systems use the Simple Mail Transfer Protocol (SMTP) to send email, and the Post Office Protocol (POP3) to receive email. When a user composes a message and clicks “Send”, the computer contacts the user's email server (typically located at an ISP) and delivers the message using the SMTP protocol. In addition to the message itself, the sending computer tells the server the email address of the message recipient.
The SMTP email server accepts the email message and temporarily stores it on its hard drive. At this point, the sending computer can disconnect from the server. The SMTP server then analyzes the message's "to" address and forwards the message to the appropriate email server at the recipient's domain. For example, if the message were addressed to "abcd@wxyz.com", the originating email server would forward the message to the email server at wxyz.com.
The destination email server stores the message until the recipient connects to the server to retrieve his or her email. When the recipient logs in to the POP3 server, their emails are delivered to their email client, and, optionally, also deleted from the server. |
