PGP (Pretty Good Privacy) is strong e-mail and disk encryption software written by Phil Zimmerman and released for free to provide strong encryption for everyone. Zimmerman's company (also called PGP) has merged with Network Associates (NAI), but a freeware version of PGP is still available at PGP Internatinal home page. PGP will automatically install support for file encryption and email encryption on Win32 platforms, and has plugins for Eudora, Outlook, and Outlook express on Win32 platforms. It also has strong Macintosh support, and many variations for Linux.

PGP provides the strongest cryptography that is publicly available and uses your choice of algorithms with key lengths up to 4096 bits. Perhaps the coolest thing about PGP is the fact that NAI maintain public key servers upon which you can store your public key for others to encrypt messages to you when they don't already have your key. That service makes PGP highly useful, and it is the reason why it's the well know and trusted encryption solution.

Encryption software directory