For a much more gentle (and illustrated) introduction do public-key encryption, GnuPG and how to use it with email (Thunderbird + Enigmail), see FSF's Email Sel

For a much more gentle (and illustrated) introduction do public-key encryption, GnuPG and how to use it with email (Thunderbird + Enigmail), see FSF's Email Self-Defense: https://emailselfdefense.fsf.org/ https://emailselfdefense.fsf.org/ Tactical Tech's Security in-a-Box has more detailed, step-by-step, multiple platform guides for the same tools: https://securityinabox.org/en/guide/thunderbird/windows https://securityinabox.org/en/guide/thunderbird/windows https://securityinabox.org/en/guide/thunderbird/linux https://securityinabox.org/en/guide/thunderbird/linux https://securityinabox.org/en/guide/thunderbird/os-x https://securityinabox.org/en/guide/thunderbird/os-x