I'd like to learn more about the various applications and interpretations of Karate katas. Is there a written source I can use?
There are numerous resources for learning various bunkai or kata. I don't know if I would consider any one of them authoritative (instead preferring this sort of classification better left to the teachings of a shihan), but they exist and there is no sense limiting that information.
- Shihan Te: The Bunkai of Kata by Paul Anderson and Darrell Craig
- Bunkai-jutsu by Iain Abernathy
- The Way of Kata by Lawrence A. Kane and Kris Wilder
- Bunkai Oyo DVD with Jean-Piere Lavorato
- Kyokushin Kata Bunkai DVDs with Bertrand Kron
- KARATE - Katas, Bunkai, Applications and Karaté Bunkais-Katas by Emmanuel Akerman (in French)
- Hidden Hands by Phillip Starr
Martial Maneuvers by Phillip Starr
[Editor's Note: These previous two books give a serious look at how moves can be interpreted, and how some movements are very deceptive and should be examined in some depth to figure out what the applications can be.]
I encourage this list to be expanded and edited by those far more knowledgable in this field than I.
One outstanding source for anything bunkai is any of the chin na books by Dr. Yang Jwing Ming. Dr. Yang has probably forgotten more than most people learn in a lifetime. He authors/teaches mainly from a Chinese (Kung Fu, Tai Chi Chuan) perspective, but once you read one of his books or view one of his DVDs your reaction will be "Dang!! That might not be my art, but I've got a move in my kata that looks incredibly similar!".
And therein lies one of the secrets of bunkai - it doesn't matter what art you train in, the opponent's body is the same no matter whether you use Kung Fu or Karate*. The application of bunkai can be adapted across styles. Even if you have yet to learn similar techniques to what he shows, he has shown you the points on the body to use and the mechanics of the move and you will find that you know other techniques that can utilise the same points and mechanics.
*Speaking broadly, the bunkai Dr. Yang teaches can be utilised in most external styles
Well, yes, there are... And that's part of the problem...
The Japan Karate Association have a number of (authoritative) publications in various formats; books, CDs, DVDs etc.
However... Much of what is taught as the meaning of kata in the official publications is nonsense. example, block a kick from your left using gedan barai. Simultaneously block a low kick from the front and a high punch from the rear.
Either, they don't know the real meaning of the movements in kata, or they are unwilling to put the real meaning into print or video.
If you go back further, you find that early publications by Funakoshi did contain real, credible applications for sequences within kata (e.g. Karate-Do Kyohan 1935 edition), only for them to be removed in later editions of the same books. Obviously not by accident. The consequence of this is that now these early editions are excruciatingly expensive and very difficult to get hold of.
So, yes there are "authoritative" resources out there, but they are not as useful as one might imagine.
There are other non authoritative resources though which can help explain kata, applications etc. They are usually not Shotokan specific, and there is no real reason for them to be.
"Bunkai Jutsu" and "The Way of Kata" are already listed by other answers. Highly recommended. Anything by the authors of those books should be read and on your shelves. Web sites and DVDs etc are also worth acquiring.
One of the most important books published, but not listed and relatively unknown outside the Goju-ryu community is "Okinawan Goju-Ryu II: Advanced Techniques of Shorei-Kan Karate" by Seikichi Toguchi. It's referenced by "The Way of Kata" and is a must read for all karateka.
Finally, because there are really no trustworthy authoritative sources, there is http://katapedia.org/. Which is my attempt to remedy the situation.
No. To avoid such knowledge being used by the wrong people, it is kept hidden and only shared to students. It's fair to assume that some particularly effective applications are not taught to people who haven't reached a certain rank.
The Way of Kata will help you learn to think about the moves in your forms and how they can be interpreted. It is well-written and will get you started, but it is not the be-all, end-all of form interpretation. I recommend you also study the following two books:
Be responsible, study, practice, meditate.
Iain Abernethy has some good information online relating to Bunkai:
And also in video form: