Introducing qmail

Abstract

Andy wants to send an e-mail message to his friend Josh. He opens his mail client, clicks on New Mail, enters Josh’s address in the To field, fills in the Subject field with a short description of the message, and types the message into the large editing area of the form. When he’s done, he clicks on the Send button. As far as he’s concerned, the message is sent, but behind the scenes, complicated machinery whirs to life. A thousand tiny steps will be executed on Andy’s behalf by processes on various systems between Andy and Josh—who could be in the same room or half a world away