PGP stands for Pretty Good Privacy, and GPG stands for Gnu Privacy Guard. PGP came into the scenario around 1991, and was taken into the official mould with RFC 2440 and RFC 4880. It uses a combination of public-key and symmetric cryptography in order to make sure that no third party can access the contents of the message. In order to secure the source of the message it takes the sign of the sender (author). While there are various algorithms used for encryption, the most commonly used methods are RSA for the public key crypto and AES for the symmetric cypher. It is very crucial that the public key of any of the parties is verifiable in order to ensure that the message is correctly delivered to the right person or is from the right sender. Here we have a basic guide for using PGP/GPG for windows.