Reading Email Headers

This document is intended to provide a comprehensive introduction to the behavior of email headers. It is primarily intended to help victims of unsolicited email ("email spam") attempting to determine the real source of the (generally forged) email that plagues them; it should also help in attempts to understand any other forged email. It may also be beneficial to readers interested in a general-purpose introduction to mail transfer on the Internet.

Although the document intentionally avoids "how-to-forge" discussions, some of the information contained in it might be turned to that purpose by a sufficiently determined mind. The author explicitly does not endorse malicious or deceptive falsification of email, of course, and any use for such purposes of the information contained in this document is contrary to its purpose.