The Pretty Good Privacy (PGP) cryptographic software
PGP was created by Philip R. Zimmermann in the early 1990's, partially in response to plans by the US Government that would force all cryptographic software to have "back doors" for government agencies. Because the program was made available to non-US citizens, Zimmermann was accused of violating export regulations concerning 'munitions' (which cryptographic software was considered to be at the time). The investigation was later dropped.
PGP started out as freely available software. In 1994 a company called Viacrypt obtained the right to sell PGP. This company later turned into PGP Inc., which was subsequently acquired by Network Associates. NA spun out the PGP technology into a separate company called PGP Corporation which today is the official seller of PGP. An open source alternative is available in the form of the GNU project's GNU Privacy Guard (GPG).
- The passphrase FAQ
- The PGP Attack FAQ
- Handson Cryptografie: Cryptografie met Pretty Good Privacy (in Dutch)