Before the beginnings of the web, E-mail was, and still is, the most popular feature of the Internet.
The way E-mail is delivered in a manner slightly similar to transfering a web page, but with a few notable differences.
When you click on the 'Send' button, the first thing that happens is that the message is copied to your ISP's Mail Server. When that's done, the mail appears to be sent, but that's just the beginning of the operation.
After the Mail Server identifies who the message is from, it time stamps it and begins to access the remote mail server. (Bellsouth's Mail Server is mail.atl.bellsouth.net. MindSpring's is mail.mindspring.com.)

When the two mail servers connect, your message is transfered over the Internet, usually going through no less than 10 seperate hubs (called routers) to reach its destination. When your message is on the recipient's Mail Server, he or she can access it whenever they check their mail. After their mail is checked, the message is deleted from the server.