Before I read this book, I didn't know the first thing about string theory, general relativity or quantum mechanics. I believe people like me were the author's target audience; that is, people who are profoundly interested in the mysterious physics of the universe, but lack the scientific or mathematical background to understand them in their raw form. This book certainly shouldn't be seen as anything other than an introduction for those of us outside the field of physics.<br><br>Each chapter in this book lays down the foundation for the next chapter. Greene manages to group together scattered discoveries from the past century or so according to their relevance to the topic at hand, and it feels very natural. Every complex concept is explained in somewhat technical detail and then followed up immediately by a clever (and occasionally humorous) analogy. The key points are always restated and rephrased to make absolutely sure the reader is on the same page with the author. This method really does wonders for nailing important concepts to your head, which turns out to be absolutely essential as the book progresses and new ideas are stacked atop the old.<br><br>This book, overall, is interesting. There are some extraordinarily intriguing chapters that will have your mind racing for at least a couple days, trying to piece together the chapter's implications, and then there are a couple dull chapters that almost feel like a chore to get through. However, the dull chapters, which seem to be flooded with basic mathematical and technical details, are necessary to understand the big picture. Greene only presents us with the details we need to understand, nothing more, and I honestly can't think of a way he could have made these dull chapters exciting.<br><br>If you are a curious physics newbie, or only know bits and pieces about the basic concepts of string theory, special and general relativity, quantum mechanics, black holes, the big bang, or hidden dimensions, this book is certainly for you! If you are already knowledgeable in these subjects and seek the deepest technical and mathematical information about them, I'm guessing you will not find what you are looking for in this book.