Pretty Good Privacy

In computing, encryption program that runs on personal computers and is distributed on the Internet free of charge. It was written by Phil Zimmermann and released to the Internet in 1991 amid growing fears that the USA would pass a law requiring all secure communications systems to incorporate a ‘back door’ to make it easy for law enforcement officials to read encrypted messages.

PGP is based on the RSA algorithm and uses public-key cryptography; its source code has been released to the cryptographic community for study and testing. Since version 1.0, its development has proceeded in multiple locations around the world to avoid conflicts with the US laws banning the export of strong encryption. A companion product, PGPfone, released in 1996, runs across the Internet to give users the equivalent of a military grade secure telephone.

In 1996, Zimmermann founded PGP Inc, which was acquired by computer security software developer Network Associates in 1997 to sell a version of PGP for business use. In October 2001, Network Associates decided to fold part of its line of PGP security software into its McAfee division, and to seek a buyer for the file and desktop PGP application. No buyer came forward, and in March 2002, Network Associates stopped selling its PGP Desktop software. A freeware version of the program continued to be available from the International PGP Home Page.