As I understand it, PDF was a proprietary file format that was closely guarded by Adobe - you didn't see non-Adobe programs that could do anything with PDF until just recently, although WordPerfect and a very few (non-Microsoft) programs were able to save (but not edit) files in PDF format.

Then Microsoft came up with its own XPS format, which it proposed as an open standard that did more-or-less the same as PDF. Just after Office 2007 was release, Adobe allowed Microsoft Word to save files as PDF. That probably kills the new XPS format, but I suppose Microsoft won't really care because what they really wanted was to get access to PDF.

I've been having problems with PDF files lately because recent versions of Adobe Acrobat Reader seem to have the tendence to hang or crash. I'm very happy for Bill's PDF-XCHANGE VIEWER because the program seems to operate very smoothly and isn't the memory hog that Acrobat is. Maybe that software firm should pay Bill some royalties.

....and to think that just a few short years ago, Bill was the last person on earth using Windows 3.1....

-Joe-