PGP stands for Pretty Good Privacy. It is a tool for encrypting email and computer files using a technique called public key encryption. It is the de facto world standard for email encryption. You put your private correspondence in envelopes rather than sending it on postcards.
Email is the electronic equivalent of postcards.
In going from here to there, email passes through many servers and routers, with the possibility of being read at each one. If you were writing to me concerning a problem with your medical treatment, you would probably prefer that only I could read your message. You publish your public key to the world while keeping your private key secret. For a clear and fairly concise detailed explanation, please click here . PGP comes with plug-ins to seamlessly integrate it into all of the common mail programs.