"If all the personal computers in the world - 260 million - were put to work on a single PGP-encrypted message, it would still take an estimated 12 million times the age of the universe, on average, to break a single message.”

  PGP 9.0 was released on 5/10/05 (PGP 9.7 is the current version as of this writing).  Some of the major changes include an Email Proxy instead of email plug-ins (email encryption is now quite automatic/transparent and very configurable, and is also compatible with a far wider variety of email clients, including my favorite - Pegasus Mail), Whole Disk Encryption, and AOL Instant Messaging encryption.  PGP Desktop Professional compares to the PGP 8.1 Workgroup Desktop, and is the PGP 9.x Desktop product that also includes Whole Disk Encryption.  PGP Desktop Home compares to the PGP 8.1 Personal Desktop, but lacks smart card support.  There is a free Trial version that is full functioning - when the free 30 days expires, it becomes comparable to the PGP 8.1 Freeware - the Trial Version also offers the option of directly installing it as the Freeware.  PGP 9.7 for Windows supports "Microsoft Windows 2000 (Service Pack 4), Windows Server 2003 (Service Pack 1), Windows XP (Service Pack 1 or 2), Windows Vista (all 32-bit and 64-bit versions), Microsoft Windows XP Tablet PC Edition 2005 (requires attached keyboard)."

PGP 8.1 products included PGP Freeware (lacks PGPdisk; has no plug-ins; lacks smart card support; may not be used commercially); PGP Personal Desktop (named PGP Personal in PGP 80 to 8.0.2; adds PGPdisk, smart card support, and email plug-ins for Eudora, ICQ, Outlook Express, and Outlook; may be used commercially); PGP Workgroup Desktop (named PGP Desktop in PGP 8.0 to 8.0.2; additionally adds email plug-ins for GroupWise and Lotus Notes, and adds support for Exchange Server environments in Outlook); and PGP Corporate Desktop (named PGP Enterprise in PGP 8.0 to 8.0.2; additionally adds PGPadmin and PGP Keyserver).  Although PGP Freeware and PGP Personal Desktop have perpetual licenses, the default licenses for PGP Workgroup Desktop and PGP Corporate Desktop expire after one year.

NAI had produced both Personal Security and Corporate Desktop (previously named Desktop Security) versions that can be used commercially, and include PGPdisk for disk encryption.  As of March, 2002, NAI had announced that they were discontinuing the product, due to insufficient profits.  They had stopped selling both PGP Corporate Desktop (their last version is 7.1.1) and PGP Personal Security (the only version is 7.0.3 - the 5.5.x and 6.x versions were named Personal Privacy).  The only PGP 7.x Freeware is PGPfreeware 7.0.3 (for noncommercial use).

   PGP International "i" versions were for the rest of the world.  These versions were created from the legally exported printed source code (PGP source code is released in binary form as of PGP 6.5.8) of the official versions.  They were basically the same as the official versions, but free of USA patent restrictions and tended to have RSA compatibility that some official versions lacked.  PGP freeware versions and source code can be found here.  Please note the following from the PGPi site:

"[13 Dec 1999] US Government grants NAI export license for PGP: Network Associates, Inc. today announced that it has been granted a full license by the U.S. Government to export PGP world-wide, ending a decades-old ban on the export of strong encryption products.  The license, effective immediately, marks the end of the PGPi scanning and OCR project, which started with PGP 5.0i in 1997."

QDPGP "is a PGP plug-in for Pegasus Mail (Win32).  It is 'freeware' and may be used and copied, without fee or obligation, for private or commercial use."  With PGP 6.x and above, QDPGP allows you to use the improved signature hash functions of SHA1 and RIPEMD160 with RSA keys.  With PGP 6.5.x and above, QDPGP "Supports synchronization with KeyServers when encrypting/verifying messages."

PM-PGP  "This software (Win95 through WinXP) enables You to easily integrate PGP into Pegasus Mail and protect Your personal communication against unauthorized access.  It contains a special feature ("AutoPush") that automatically initiates the encryption process for selected addresses provided by a user-edited list.."

PGPfone "is PGP for voice PC to PC over the Internet."

PGPClick is a Windows program which provides easy access to the DOS-based 2.6.x versions of PGP.  I was amazed that this gives users of 2.6.x the same as my then favorite PGP 6.0.2 feature, the Use Current Window functionality.

PGPsendmail "provides for automatic encryption and decryption of Email messages, using PGP."  I'm told that this is a way to use PGP from your web site; and that the included documentation tells you how to set it up.

Eraser "consists of several utilities built on top of a powerful file wiping library capable of securely removing sensitive data from your hard drive."  Included is "a scheduler which allows you to program the erasing of unused disk space or, for example, cache files to happen regularly, at night, during your lunch break, at weekends or whenever you like."

ScramDisk offers free (for Windows 95/98) high security disk encryption.

Swap File Overwriter "overwrites the swap file, invalidates its file pointer, zeroes its date/time stamp and safely deletes what is left."  Using Scorch, this is done easily and quickly when shutting down or restarting Windows 95/98 (but not Windows ME).