The GNU Privacy Guard version1: Encrypts, Decrypts, and Signs Data
The GNU Privacy Guard is an OpenPGP (RFC2440) implementation. It allows encryption, decryption, and signatures of data and contains strong cryptographic algorithms. It is most often used with mail. It is not to be exported or reexported from the US. It is not to be used in certain countries. Please check the laws. As of version 1.0.3, support for RSA has been integrated into GnuPG, as the patent encumbrance expired 2000-09-20.
This is version 1 of gpg, which still supports modules for encryption.