This document is a HOWTO for the Postfix Mail Transfer Agent (MTA). Postfix is being developed by Wietse Venema and Licensed under the IBM version of the GPL. The Postfix Web site is at http://www.postfix.org. As of this writing the current release of Postfix is 19990906 Patch Level 7. What is Postfix? In short Postfix is a Mail Transfer Agent (MTA) but to provide a better answer to that question here is a quote from the Postfix Web site:
"It is Wietse Venema's attempt to provide an alternative to the widely-used Sendmail program. Sendmail is responsible for most of the e-mail delivered on the Internet. With an estimated 100 million users, that's billions of messages daily. A stunning number. Postfix attempts to be fast, easy to administer, and secure, while at the same time being sendmail compatible enough to not upset existing users."