How to Encrypt Gmail messages with GPG and FireGPG

This tutorial will show how to use GPG and the FireGPG plug-in to encrypt and decrypt messages in Gmail. GPG is an open source implementation of OpenPGP (Pretty Good Privacy) , a public-key-encryption system. With public key encryption you don?t have to give away the secret key that decrypts data for people to be able to send you messages. All senders need is the public key which can only be used to encrypt, this way the secret key never has to be sent across unsecured channels.