Quantum physics has turned our commonsense notion of reality on its head. This accessible book describes in layperson's terms the strange phenomena that exist at the quantum level--a world of tiny dimensions where nothing is absolutely predictable, where we rethink causality, and information seemingly travels faster than light. The author, a veteran physicist, uses illuminating analogies and jargon-free language to illustrate the basic principles of the subatomic world and show how they explain everything from the chemistry around us to the formation of galaxies. He also explains how scientists and engineers interact with this nebulous reality and, despite its mysteries, achieve results of great precision. Up front is a brief history of the early 20th-century "quantum revolution," focusing on some of the brilliant individuals whose contributions changed our view of the world--Albert Einstein, Niels Bohr, Paul Dirac, Werner Heisenberg, Erwin Schroedinger, and others. The work concludes with a discussion of the many amazing inventions that have resulted from quantum theory, including lasers, semiconductors, and the myriad of electronic devices that use them. Lucidly written, this book conveys the excitement of discovery while expanding the reader's appreciation for a science that explores the basis of everything we know.