Technology is becoming molecularly precise. Nanotechnology, otherwise known as molecular engineering, will soon create effective machines as small as DNA. This capacity to manipulate matter -- to program matter -- with atomic precision will utterly change the economic, ecological, and cultural fabric of our lives. This book, which is accessible to a broad audience while providing references to the technical literature, presents a wide range of potential applications of this new material technology.The first chapter introduces the basic concepts of molecular engineering and demonstrates that several mutually reinforcing trends in current research are leading directly into a world of surprisingly powerful molecular machines. Nine original essays on specific applications follow the introductory chapter. The first section presents applications of nanotechnology that interact directly with the molecular systems of the human body. The second presents applications that function, for the most part, outside the body. The final section details the mechanisms of a universal human-machine interface and the operation of an extremely high resolution display system.