When and how did the universe begin? Why are we here? Why is there something rather than nothing? What is the nature of reality? Why are the laws of nature so finely tuned as to allow for the existence of beings like ourselves? And, finally, is the apparent "grand design" of our universe evidence of a benevolent creator who set things in motion, or does science offer another explanation? The most fundamental questions about the origins of the universe and of life itself, once the province of philosophy, now occupy the territory where scientists, philosophers, and theologians meet, if only to disagree. In their new book, Stephen Hawking and Leonard Mlodinow present the most recent scientific thinking about the mysteries of the universe, in nontechnical language marked by both brilliance and simplicity.