Editor's Note: At Seybold's first European incarnation of its PDF Summit, a two-day event taking place this week in Amsterdam in The Netherlands, James C. King of Adobe Systems will offer a personal look back at 10 years of PDF, with a look toward its future. His keynote presentation is the latest in an ongoing series of public talks on Adobe technologies that King, working in Adobe's Advanced Technology Group (ATG), has given over the past decade. In part because of his public appearances and his group's role, people sometimes have assumed he's played a larger role in the actual development of Acrobat and PDF than he actually has, he told Planet PDF in a recent interview. But ever since he "got it" early on, he's become an avid evangelist, proponent and user. And King and the ATG have made key contributions to the evolution of Acrobat and PDF, which were initially released June 15, 1993. But prior to the launch, King says, the software and format were being used extensively inside Adobe -- even though in its earliest days, there were some who believed the technology should be killed off (even for a period after the public release). Ten years later, he's glad the vision of Adobe co-founders John Warnock and Charles Geschke prevailed, as he explains in the following interview conducted late last week.
PLANET PDF: Jim, we appreciate having this chance to talk with you before you head off to be the keynote speaker at the Seybold PDF Summit in Amsterdam. You're scheduled to talk about the first decade of Acrobat and PDF, which Adobe Systems Inc. officially kicked off on June 15, 1993 with the release of version 1.0 of the now well-known and widely used software and file format. We'd like to hear about some of the highlights as seen from your perspective as the former director of the company's Advanced Technology Group (ATG) and currently A Principal Scientist, but first we'd like to learn a bit about your background. Please tell us about your relevant experience, education, and work history prior to joining Adobe in 1988.
DR. JAMES KING: "I was one of the first people to get a Ph.D. in Computer Science. I got it from Carnegie Mellon University in 1969. People had gotten degrees studying computers before, but in electrical engineering or something like that. I was one of the first wave from an officially established department that graduated people with those words actually on their diploma. I wrote my first computer program in 1959.
I immediately went to IBM T. J. Watson Research Center in New York, and worked there for about eight years. At that time I was working on proving programs correct and more esoteric subjects about software development and methodology. I gave talks at the Software Engineering Conferences then. Then I transferred to IBM Research in San Jose, California. After a while -- around 1979-80 -- I got interested in laser printers, when some of the first ones came out, including some of the first desktop laser printers. I got involved in making printer controllers, designing page description languages, working with fonts and things like that. I built up a group at the IBM Almaden Research Center called the I/O Systems Lab. We actually built a controller for an existing IBM printer that could do all kinds of fancy stuff. We manufactured and sold them internally within IBM. I made a bunch of money for our department. We made a hundred of them. That was a lot of fun -- it was like being an entrepreneur and a researcher at the same time.
It happens that [Adobe co-founder, chairman and former president] Chuck Geschke also went to Carnegie Mellon during the timeframe I was there. In 1988 when I was interested in leaving IBM, I called up Geschke and asked him if there was a place for me at Adobe. He said, 'Well, you'll have to come interview and meet John [Warnock, co-founder, chairman and former CEO]. No favors.' You kind of wish you could get some favoritism, but it didn't work in that case.
I built this group of people at IBM that was actually doing similar things to what Adobe was doing -- fonts, print controllers, page description languages and so forth. Adobe was doing it amazingly better, I must say! We had learned about PostScript and were studying it. In fact, I was the advocate at IBM for us *not* licensing PostScript from Adobe, but doing our own. When I interviewed with Adobe, one of the chief sales and marketing guys really quizzed me about that. He said 'How can you come to work for us when you've been working against us within IBM?' I said 'Look, I'm loyal to my employer. If Adobe is my employer, I'll do what I think is in the best interests of Adobe, but when IBM was my employer, I was saying and doing what was in the interests of IBM.'"
PLANET PDF: When, why and in what role did you come to Adobe? What responsibilities and types of projects did you first get involved with?
KING: "What they offered me at that time was a job managing a new group called the Advanced Technology Group (ATG). There had been what was called a skunkworks group of about five people that worked for John Warnock, but Adobe wanted to start another group. There were three top technical guys identified who were sort of manager-less, so they offered me the job of starting this second group called ATG with them. We initially we were four people, but after a short time we merged it with the Warnock group. By the end of the year there were more than a dozen people in the group.
The interesting thing is that I did not report to John Warnock at that time, I reported to the VP of Engineering, who was the guy doing all the printer stuff. I had always wanted to do more programming and I figured if I had three people working for me, I could do that. But until more recently I never got back to doing much programming.
I stopped being the head of ATG in 1996 -- at that time we had about 40 people. I had also started the internal Adobe library -- I hired a librarian, and that got built up to be about five people. I also personally managed our patent program for a while. But today, Tom Malloy is the VP in charge of ATG and I work for him."
PLANET PDF: Tell us about your current job and role, particularly as it relates to Acrobat & PDF.
KING: "My job title is A Principal Scientist; I'm a strategic technical consultant. Basically what that means is that I do technical reconnaissance. I'm a scout. The executives always seem to have at hand people who do business and marketing research. We have a modest group of people who do that. For example, somebody might ask 'How many PCs were sold in the U.S. last year' and they're capable of coming back with good, accurate answers, and maybe even in reading between the lines to explain about what's going on. They felt the need to have someone do that with technical topics, and they usually turn to the ATG for such things.
When Warnock and Geschke were here every day. it was pretty easy to turn to them because they were very knowledgeable about these things. They did a lot of outside discussion and communication with other technical executives, so they brought in a lot of information. More recently we've turned more and more to the ATG and the head of that group, Tom Malloy, and he was finding himself just getting swamped with these kinds of requests. He decided to set up an official job position -- so that's what I've been doing for about a year. Before that -- from 1996 until last year -- I was programming. I had decided I wanted to learn more about programming for Windows and how to build applications, so I did some programming. During that time (with some other people) I wrote an SVG-to-PDF converter that is actually shipping in the Adobe Document Server, and also is a hidden part of some other products."
PLANET PDF: How much of your programming experience was related to the Acrobat/PDF technologies at Adobe? At what point did you become involved in the early development, and what interested you in the concept and/or technology at that time? Did you envision the kind of success and popularity Acrobat and PDF have today -- that it would become the company's leading product?
KING: "Well, that's pretty interesting. I think that Chuck and John had the idea of 'soft printing,' or what we now call 'ePaper,' from an early stage. Finally about 1990, Adobe's technology and the PC technology came close enough together to make a run for it. At that time Adobe had PostScript and display PostScript, and the ATG that I was managing at that time was almost completely consumed with PostScript. We did so some work on Illustrator, and Photoshop was a new thing and we didn't really have much work to do there. We had become enamored with the idea of making PostScript Level 2, and that was an idea that came out of the ATG when we were trying to solve several different problems. We decided that coming out with a whole new level of PostScript that did everything was the right answer. But we had a hard time convincing the rest of the company. So we started doing it ourselves, just to push it forward while we could get everybody else lined up. It also added a lot of new technology like JPEG and color management that the ATG programmed and championed.
In that period we were very, very busy with PostScript Level 2. And in addition, PostScript was a big, heavy thing. Compared to the machines at that time, it was an all-consuming application. We had a very difficult time getting PostScript to run efficiently on the PCs of that time. We ran it mostly on workstations or inside printers, which usually had a better computer in them than the desktop computers did. When John wanted to build something that would work on a PC -- and they were about a thousand times less powerful than they are today -- we had made some runs at this within the PostScript group and within the display PostScript group. He knew what the group was capable of and what it was not. He actually turned to other people when he wanted to get Acrobat prototyped; he did not come to the ATG. He got some people who knew Illustrator, and took the rendering engine out of Illustrator, which ironically had been stolen from the PostScript interpreter earlier. He started a very small group of two or three people who started prototyping, so the ATG wasn't involved. There was an effort to keep us away from it for fear we'd bring all this big, heavy, fat software, and he wanted this skinny and light.
The first version was about 90 KB. It didn't do a lot of things, and there was tension there because the ATG and the PostScript group were saying 'Well, that doesn't do images,' etc, because that didn't compare to their maybe 1 MB of code. There was some jealousy and some back-and-forth. So in fact the ATG's and my involvement in Acrobat in those early days was quite limited in what we did. In addition, as I said before, we were very consumed by trying to get PostScript Level 2 out the door. That was a huge effort.
After a while we got very interested in Acrobat; the ATG has made a lot of contributions to Acrobat since the rocky start.
I recently found a memo I wrote in December 1993 describing how Acrobat forms should work. In fact, Acrobat forms today work much like what I described in 1993. We started implementing it within the ATG. We worked on it well over a year, maybe two years, and then moved the group into the Acrobat group, and it got finished and came out with Acrobat 3. That was one of the developments I was personally involved in.
We also did a lot to do with pulling words out of PDF files. You know that within a PDF file the text may have ligatures and hyphenation and all kinds of rendering artifacts. One of the people in the ATG did a lot of work on how to 'undo' those kinds of things -- to use heuristics to try to build paragraphs back up again. It's become known as 'Wordy' -- a piece of software that took text that had too much presentation material in it to look like a good text stream and undo all of that. That's been a part of Acrobat since release 2.
Most of the stuff that's been done by our group or by me is always in conjunction with the Acrobat team. Some of it's been done more independently, but we've contributed a great deal. Web Capture was a partnership between a guy in the ATG and one of the guys in the Acrobat group. I probably shouldn't list these things for fear of forgetting some of the important ones. We had another person in the ATG who got really interested in the World Wide Web -- Acrobat came out before the Web -- so he spent a lot of time and demonstrated making Web links inside PDF files, he demonstrated that you could link from a PDF outside to a Web browser, and that was a big deal. We also protyped reflow -- tagged PDF.
My view of Acrobat and PDF has always been from the ATG. I've never been a part of the Acrobat group, which has a very strong, independent development team that really has strong control of the product and that does a great job."
PLANET PDF: Seeing the popularity of Acrobat forms today, it must be rewarding to have been involved in developing the concept, and in watching the gradual -- but continuous -- growth in acceptance over the successive versions of the software and PDF specification.
KING: "Yes, but it's taken an awful long time. It first came out in version 3, and it just has taken this long to build up enough features in it and strength. The world is ready for it now, whereas earlier the need wasn't there as much as it is today.
Another thing about Acrobat in general is it took a long time for people to 'get it.' We're still facing it 10 years later. You talk to people and they don't get it. And that happened inside the company, too. In the timeframe from around 1990 until it first shipped in 1993, there were still a lot of people within the company who had a hard time getting it. And it took -- for everyone in my group, for example -- maybe a year or two after Acrobat was out there until they all got it. I was very interested in it and I think I 'got it' earlier than a lot of people. Once I 'got it' and shared the vision, I expected everyone else to get it and buy Acrobat. I think we were all a little disappointed at first. But that strong faith in the vision of where this would all lead made Chuck and John stay with it as a company. I'm glad they did.
The best way I learn things is by talking about them and by giving presentations. I've always given a lot of outside public presentations explaining our technologies. So fairly early on I started talking about and giving public presentations on Acrobat and PDF. The public has gotten the impression that I had a lot more to do with it than I actually had. I like to talk about it, and I use giving talks as a means to learn. I was constantly learning about it -- how it should be positioned, its strengths and weaknesses, etc -- in trying to explain it to other people."
PLANET PDF: What about the technology has evolved in more or less the way you initially expected, and what to you have been some of the more surprising or unexpected aspects -- in terms of development at Adobe and/or use by customers?
KING: "There's a very interesting thing that I think I always understood, and didn't really know what to do about it. When this was first put together, it was designed as an office tool. That was the vision. We were struggling inside the company to transmit documents to each other electronically. We were fairly advanced in 1990 in using email and in having the company completely networked, etc. We had found Acrobat to be incredibly valuable. I remember that one of our first major selling points was that we had an internal mailing list that was printed up every month, and we made around 500 copies, and delivered a copy to everyone's desk -- a paper phonebook with employee phone numbers.
When Acrobat got working well -- about a year before it shipped -- we made a PDF phonebook and put it on a server someplace and eliminated printing the paper versions, except for a few copies to put in conference rooms. We touted that we saved a lot of money by not printing the phonebook anymore. We used PDF a lot for that kind of thing internally. That's what it was designed for and targeted for. We got very involved in content management -- trying to figure out where to keep all of our PDF files, how to get them to people. We had a server that had some huge number of PDF files. We were really targeting Acrobat for this kind of use for the office.
Now the interesting thing is that the people who bought Acrobat 1.0 were the publishing and graphics professionals. Why was that? Because they were Adobe's [traditional] customers. They bought everything we did. They liked our products. And we were at Seybold conferences, which was where these people went, and that's where John Warnock announced Acrobat and gave the keynote talks. So those were the early Acrobat customers, and they got really frustrated because they didn't buy it to do office work, they bought it to do their graphics publishing and to be able to transmit jobs electronically. It didn't have a lot of the high-end PostScript features. We'd purposely taken those out to make it more light-weight and to make it easier to run on low-end PCs.
That was a struggle: the market we were after was one we didn't have very good connections to. And our loyal customers bought this thing that didn't really satisfy their needs. So we did the natural thing: We fixed it. That came out in Acrobat 3, where most of the special features you need to bring it out to graphics and professional publishing were added back in. That's when it really became a solid print publishing tool. Now, rather ironically, in the past 3-4 years, we're back to the original concept of having this be an ePaper product. It's come full cycle.
At the time Warnock was giving his keynotes at Seybold and everything, I was scratching my head as to why he was doing that. I actually warned people that 'these people are going to be upset because it doesn't have the features they want.'
The wonderful thing is that our loyal customers from the graphic arts community funded the development of Acrobat by buying it and using it, and pushed us hard to improve it and to add more features. They essentially helped us through the hard period. There was a real struggle the first 2-3 years for Acrobat to make enough money to sustain itself, and to justify its further development at Adobe. And that was a big struggle -- there were people inside that wanted to kill it. The loyal graphics art customers kept it alive by buying it, even though it didn't really work very well for their professional publishing needs, and I'll be forever grateful for that."
PLANET PDF: From your own involvement, what has been the biggest challenge in the development of Acrobat and PDF?
KING: "I can tell you a personal challenge, although it's not shared by everybody, and it's still ongoing. I think Acrobat and PDF are a distinctly different kind of product than Photoshop, for example. Especially early on, we had a group called the Application Product Division, and they built application products. We always talked about Acrobat as being a communication product, and that wasn't to be taken lightly. In fact, the first Acrobat team was formed into the Communications Product Division. Warnock always called Acrobat a communication product, and I'm sure he still does today. He doesn't mean communications like telecommunications, he means like interpersonal communications -- how one person communicates to another through publications or writing or whatever.
When you have a communication product, it has to work everywhere the same. It's heavily built on top of a standard. For example, if I have a plug-in for my Acrobat on my desk that does something special -- and we've had a lot of pressure from companies that want to build plug-ins that do special things that made it proprietary to them -- and then I send that PDF file and there's something in it that's special, and the other person doesn't have that plug-in, they can't view it. If you take Photoshop and I have a plug-in and I do something that gives me really weird effects and gives me wonderful results and I publish those, nobody cares that I had a special plug-in for Photoshop. That's a private affair. It doesn't have to do with communication. It has to do with me making some beautiful output and getting it published. But with Acrobat, plug-ins are a completely different thing because they can disrupt the communication standard tremendously. We've had a struggle trying to make people see that this product is different from the others. There's a certain amount of interoperation guarantee that you have to preserve. The Acrobat team is constantly struggling with that as people ask for features and extensibility.
It's like having three telephones in your house -- red, blue and green; but with the red phone, you can only call other people who have red phones, etc. That phenomena you have to avoid if you're in the communication business. And Acrobat is a communication tool. I can't tell you the number of other companies that have lobbied for us to give them a way to put in some special compression technique that they have, etc., and the reason is that they would like to have a proprietary version of it. We've always found a way to avoid doing those things. That's been a kind of behind-the-scenes struggle of keeping control of PDF as a communication language and as a dependable standard that you can count on.
Our product groups are very oriented toward pleasing the customer and making a product that will sell well. That really pushes you if some other company -- especially some big, influential company -- comes to you and says 'We have this wonderful technology that we'd love to get into your product, but only in a way that we have some control over. It's really hard to resist those kinds of discussions because some of them are potentially worth a whole lot of money, and so there you're caught between weighing this lucrative deal against this intangible thing of your standard. I think Acrobat and PDF are old enough now that having it be this communication standard is not so intangible any more. It's very tangible."
PLANET PDF: At A Seybold event in 1998, you gave a very enlightening presentation called 'PDF: A Look Inside' designed in part it seems to give non-technical users a "general understanding of what kinds of things are inside of PDF files and how they are organized and relate to one another." Could you give us a brief 'look inside' a PDF file -- just set the stage for those who may not have seen that presentation yet, and to which we'll provide a link? Have you ever felt a need to update that, or is that even necessary since most of the information is still relevant?
KING: "That's a confirmation of how stable PDF has been in its basic properties. I still give that talk. It's still alive and well without any change. The basic parts of it are still very valid. That was prompted because some time ago one of the Seybold editors had written that PDF was proprietary. I wanted to try to teach him where his mistakes were so he could really understand that the stuff he was writing was incorrect."
I went to Seybold Seminars headquarters and spent a day showing some of the staff a bunch of sample PDF files I'd made. It was pretty technical -- like having someone read a reference manual to you! A couple months later they called and asked if I could give this talk to their whole (Seybold Conference) audience. They convinced me that the Seybold audience would like it, so I went ahead and gave it in New York. And it was really popular! So they had me do it a second time in San Francisco.
I didn't really do it to teach people what's inside a PDF, but to remove some of the fear and mystery. I think that works very well. Before that, many people thought that if you looked inside a PDF file, Adobe would sue you. The part I give is just the basic, simple part -- just the basic outline of the file and how you do the PostScript-like stuff on a page. I don't go into any of it in great depth. It really does give you a feel.
You can, after going through those slides, actually look at a PDF file and make some sense of it. The part that messes it all up is the compression. We take and compress large parts of what's inside a PDF file, so it's just a bunch of gibberish characters when you look at it in an editor. That makes it look really unreadable. In all the examples I used, I turned that compression off -- it's an optional thing -- and so all of the text in those files will be clear text. Once you see that you can say 'Oh, now when I see those compressed blocks [in other PDF files] I know what's in there. I know the kind of stuff that's in that gibberish.'
Once you do that [create a version without compression], it's pretty clear what the structure is. It's pretty tedious to dig through them [to view a PDF file's 'innards' with a text editor]. A PDF file is nothing but a sequence of objects, and the objects are all numbered 1 to whatever, and they reference each other by number. It's just a very general structure for a file and it gives it wonderful, powerful random access capabilities that, with an index [a cross-reference table] that's put at the end of the file (usually), you can take any object number you want and it tells you exactly where in the file it is, so you can just jump there and read just those bytes you want from the file. We display a single page out of a PDF file with only touching the bytes you need to display that page. You don't have to read any of the other bytes in the file. That's a key property. It's easy to understand once you grasp this notion that it's just a sequence of objects. What really blows your mind -- you can move the object to anyplace else within the file as long as you update the cross-reference, and it just works. There are no positional dependencies of the objects in the file. They can be arranged in any order. I find that all very fascinating. That's the kind of stuff I talk about in that tutorial. There are no secrets -- you can dig around inside a PDF file and find out everything there is to know. The talk is accompanied with about 20 sample files that I have fixed up to be more readable in a text editor."
KING: "That comes about for a very funny reason. In your day-to-day work people put together presentations very quickly, and they don't have the chance to do much with graphics. They come out with these bulleted outlines. There's also a tendency while creating a presentation to use long sentences, and to have the presentation be totally self-contained, so someone reading it later will understand it better.
I've been a student of how to give and create presentations, and I think those make about the worst visuals in the world. I decided a long time ago that I want people to listen to me speak, and to listen to my words. The slides are there to help me; for a large part they are just there to give me an outline to remind me of what I want to say. I also try to make diagrams that show how things relate and try to put those into the slides. So that means that my slides come out absolutely useless when you go to look at them without me talking. And I do have this need for people occasionally to understand them later. So I was caught in a dilemma. I refuse to make self-contained slides where someone can just read them because they are soooo ugly. And I want graphics, and sometimes you need to say things about the graphics.
I was drawn to the idea of using PDF annotations. I thought 'Why not just type in what I say and stick it on there, and then they almost don't need me anymore.' They can read what I said and look at the slides. I even have created some samples for myself that provide the audio of the same thing -- recording what I would say on each slide. It's a great idea and it works very well. I almost starting writing some code to make a plug-in to automate some parts of that. The reason I stopped is that the audio really makes the file huge. The text annotations work really well, especially when you can print them out and read them as you browse through the main presentation."
PLANET PDF: We mentioned discussion lists earlier, which reminds me of a presentation you once gave on knowledge management at Adobe Systems. You explained that the company makes extensive internal use of topical email lists as one way for small groups within the company to easily exchange ideas on a wide range of issues, including product development. I think you mentioned at the time that you belong to more than a hundred such lists, and manage several dozen. You also said that you -- not surprisingly -- prefer to use PDF as an email-archiving tool rather than some other available tools and methods, and also that it's considered 'a sin' at Adobe to send any format other than PDF as an email attachment. Can you talk a little about the communication process referenced above, and in particular how Adobe uses PDF internally as part of that?
KING: "Several years ago -- as a learning exercise for programming Windows -- I wrote an email-folder-to-PDF conversion program. It worked pretty slick and it was very good for having an archive of emails that could be searched efficiently. I had made links on each page to the next/previous mail/page by date, sender, and subject. I also made a table of contents (bookmarks) for each of these categories with the others as subordinate. So it was really easy to navigate through a set of email -- and fast. It got used by a few people internally, but now that the mail standards have evolved it not longer works well. But I did learn a lot about programming in Windows.
What you said about Adobe internally being intolerant of anything but PDF attachments is true. Every once in a while you will see a note chastising someone for not converting their attachment to PDF before sending it.
Adobe has thousands of mailing lists and I am back up to being subscribed to more than 200. We have very effective technical discussion using e-mail. It is a solid way of life for me."
PLANET PDF: The Acrobat 6.0 product family is now shipping. What enhancements or new features do you expect people are going to especially enjoy and find useful -- and why?
KING: "I'm still overwhelmed by Acrobat 6 -- it has so many features and so many new ideas. It's just amazing. I think this release might just break collaboration loose and really make it a big deal. We've had stuff in there for annotations, highlighting, etc, for many releases. Acrobat 5 had a bunch of improvements for doing server-coordinated annotations, and I think we learned a lot from that and we made some major improvements in Acrobat 6. They've made it so dead simple that I think people will really begin to use it. And they've integrated it with Word and Office in such a nice way, and I think that's going to take off. That one strikes me as about ripe to really go.
We acquired Accelio (aka JetForms) in early 2002, and a lot of their work is in Acrobat 6. We've made major improvements in Acrobat forms. It's a major sales and marketing effort on our part this year to make the world aware of how powerful Acrobat forms are, and how XML-oriented they are. I think both our technology and our marketing efforts should make forms a big deal for Acrobat 6. That's our plan.
The other thing is we now offer a professional version of Acrobat -- there are also some features in there that are going to open some people's eyes. I think we've integrated and made a smooth set of features for professional publishers, good support for PDF/X and preflight -- all integrated into the base product. I think we've done a lot for the graphics professionals with a version of Acrobat 6 that's tailored for them.
And then we also did a whole bunch of work to help the CAD (Computer-Aided Design) people use PDF more effectively for capturing drawings. Those people are very eager to get off paper -- they have such huge drawings and blueprints, and a whole bunch of special requirements that Acrobat and PDF weren't meeting in previous releases. So we had a group go off and talk with them and study their problems. So Acrobat 6 Professional also has some features for the Engineering Professionals.
This trend we have now is to concentrate on segments of professionals to give them more features, to customize things a little bit. Sometimes it's just a small amount of work that all of a sudden makes the product really worthwhile in that environment. We're hoping we've done that for Engineering professionals."
PLANET PDF: At Seybold Amsterdam you'll be reflecting back on the first decade of Acrobat and PDF. Can you give us a sneak peek at a few of the things you'll be discussing, and briefly explain the significance?
KING: "I went back and looked through all of my old slides and materials about Acrobat and PDF, and tried to pull out one slide from most of them that had to do with the most interesting thing from that presentation. I have about 15-16 of those. A big part of my Seybold Amsterdam keynote will be to look through those fairly quickly. They're a funny glimpse of the history of PDF and Acrobat -- it's very uneven -- they don't necessarily reflect the key features of the product, they only reflect on what I was compelled to talk about at the time. They hit some high points, too. I hope the audience enjoys it -- it's kind of a selfish thing, but I got a big kick out of doing it. I will also try to speculate about the what the future holds."
PLANET PDF: Speaking of reflecting and speculating, we've enjoyed this chance to catch up with you. Thanks for making time to share your invaluable insights with the Planet PDF community, Jim!
OK, so you want to stamp your document. Maybe you need to give reviewers some advice about the document's status or sensitivity. This tip from author Ted Padova demonstrates how to add stamps with the Stamp Tool along with related comments.