In this article, you'll learn how to install, setup, and use the Mozilla Thunderbird email client for secure, encrypted email using GnuPG and the Enigmail Mozilla Thunderbird extension. The examples in this article are based on Ubuntu 5.10, but any GNU/Linux-based operating system can be used. You’ll also get to tackle the basics of using GnuPG with Enigmail—just enough to get you started, as GnuPG is a very powerful suite that can extend to other applications. If you'd like to learn more about cryptography using GnuPG, the man pages are a good place to start. Don’t worry though, GnuPG is very well documented and you'll be presented with some links online at the end of this article to get you started.