I wrote just a second ago:

> Lane Rollins writes:
>
>  > As a kind of a side question... I know that PDF is based off Postscript,
>  >  does anybody know of a document that defines the layout of a PDF file?
>
>  The copies we have are: "Portable Document Format Reference Manual",
written
>  by Tim Bienz & Richard Cohn, Adobe Systems Inc., June, 1993, First
Printing,
>  published by Addison-Wesley, ISBN 0-201-62628-4, marked $24.95 (but
> obviously subject to change during the last six years).
>

While engaged in an unceasing and relentless pursuit of the truth, I signed
onto the Amazon web site to see if the book I referenced above is still
available. It is -- and the good news is that the price has been reduced.
However, the better news appears in one of the reviews for the book:

=======================================

[log in to unmask] from Germany, April 30, 1998

Absolutely not up to date! While in structure and content up to par with other
Adobe books, this book should be taken off the Amazon shelves! It is
completely out of date, and you can download the newest version of the PDF
specification from the Adobe web site -- free of charge!

========================================

Leaving no tern unstoned, it took me a bit of time to find the PDF manual at
the Adobe site, but it appears to be at:

http://www.adobe.com/supportservice/devrelations/PDFS/TN/PDFSPEC.PDF

The manual is downloading as I type this, but it does look like it is going to
be the correct document.

Wirt Atmar