GnuPG is GNU's tool for secure communication and data storage. It can be used to encrypt data and to create digital signatures. It includes an advanced key management facility and is compliant with the proposed OpenPGP Internet standard as described in RFC2440. . GnuPG does not use any patented algorithms. This means it cannot be compatible with PGP2, because that uses IDEA (which is patented in a number of countries).
