Slashdot Mirror
Before PDF: John Warnock's 'Camelot'
Karl De Abrew writes: "In the Spring of 1991 Dr. John Warnock wrote a paper he
dubbed "Camelot" in which the Adobe Systems Co-founder and
CEO laid out the foundation for what has become Acrobat/PDF.
With the author's permission, Planet PDF is pleased to publish
the full-text of that historic document." Of course, now it's 2002, and the dream of universal display / printing remains only partly realized; PDFs really have helped to narrow the gap between dream and reality, though.
In my opinion, it isn't truly good until it can be freely converted back and forth into other usable, edit-able formats.
Which, I note, thanks to the efforts of many, is a criteria that even Microsoft Word doc format is able to meet.
Also while the pdf format is controlled by Adobe, the specs are open and available (contrast this with Microsoft's format which is a complete mystery), you can get the specs from Adobe's site and nothing prevents you from writing code that manipulates pdf files (well yes there are issues with compression algorithm).
This openess is the reason why Apple chose to use pdf as their graphic description language for OS X (older OS versions used QuickDraw). The windows page description language, is, I think, WMF. It's funny to think that the basic page description language used under Unix is Postscript, which is much more closed than PDF.
I don't think you know what you're talking about! I'm not an expert by any stretch of the imagination, but I think there a few things to consider. My understanding is that it's "Adobe PDF" and it's a de facto published "standard" controlled by Adobe. PDF is a derivative of PostScript Level 2. It is most definitely proprietary even though the format specification is available. Usually when people say "open standard", they mean that it is a "de jure" standard controlled by a recognized standards body like ISO, and Adobe Systems is a single interest, not a standards body. Another usage of "open standard" with respect to Adobe PDF refers to the fact that it's published and royalty-free. If Microsoft publishes the Word document format, it is still a proprietary format.
The problem with proprietary formats like PDF is that a company who wants to influence the standard cannot join the controlling standards body. So basically if you don't like the direction Adobe Systems is taking with their format, you're screwed unless you have clout with the company. If you're concerned with archiving information for a long period of time or choosing an interoperable format, the proprietary nature of PDF is discouraging.
Don't get me wrong, I like using the PDF format and have produced some nice documents using pdflatex, ebnf2ps, and other free PostScript tools. I just think it's important to understand the limitations of PDF which are primarily that it is 1) a publishing format more than an editing format and 2) Adobe controls it. At work, for example, documents are stored and passed through an editing and publishing workflow as XML, archived as XML, and only rendered to PDF on demand at the end.
I hate to ramble on, but there seems to be a lot of misunderstanding on this topic. Some other people have made the analogy between the JPEG graphics format and a format with layer information like Photoshop's proprietary format. PDF is not designed to carry the types of metadata you might want in a document workflow as well as XML (or SGML), just like JPEG only represents the final rendered and flattened ("published") image from what may have been a multilayer graphic in the editing process. In other words, PDF is not a universal document format when you are concerned with editting or automation which relies on metadata that is not part of the document displayed to a user.
-Kevin
and the biggest advantage of PDF:
I'm sure there are other differences, but even many people I know simply use pdfLaTeX now to generate PDFs from LaTeX markup instead of the old DVIs, so presumably even they see an advantage in Adobe's format. When it comes down to it, I suspect that PDF's font embedding, better handling of other embedded content, and on top of that simply its pervasiveness are the biggest factors. Anyone is welcome to correct me on any of this, however.