An Introduction to GNU Privacy Guard (Part 1)
GNU Privacy Guard, or GnuPG (http://www.gnupg.org/), is the open-source equivalent of Philip Zimmermann's PGP (Pretty Good Privacy) encryption/authentication software released under GPL. Philip Zimmermann and others developed PGP in 1990 using the Rivest-Shamir-Adleman (RSA) public-key cryptosystem to answer the need for private and secure communications between individuals over digital medium. After its release to the public in 1991, it quickly grew to become the de facto standard worldwide for secure public-key encryption.
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