While the technical specification of JSTL is readable like most hi-tech documents are "readable" (i.e. it left me sometimes a bit puzzled), this book is both deep and full of very useful examples. Sometimes, in my opinion it goes too far (programming a message board with JSTL), but this only goes to show how powerful JSTL really is.Overall, I really enjoyed reading it: It made a lot of things clearer and there were a couple of times where I thought: "Oh, I didn't know that JSTL could do that!".