This book is written for middle and high-schoolers with little or no knowledge of basic scientific principals. If that's you, then this text may serve you well. However, for those of us with a strong scientific background, this is, possibly, worse than a Dummies book. It is very rudimentary and written for 12-18 year-olds. However, for a more mature treatment of the subject, I recommend Scherz and Monk's Practical Electronics for Inventors.
Update: I think I spoke too soon. The introductory, chemistry part is fairly elementary but the other parts have good explanations for any education level. Of some relevance, I suppose, is the fact I stopped reading the Monk text and switched over to The Art of Electronics, which is pretty dense, and this book is a good companion.