This guide aims to explain the basic scientific principles behind high-tech concepts, describes how these systems work and discusses how they impact our lives. Topics in this updated edition include: biotechnology, micromachining and nanotechnology; circuits, microscopes, pl anetary spacecraft, radar; high definition television (HDTV); Internet and World Wide Web; virtual reality; sheep cloning; defeat of world chess champion by a computer; and cryogenics and chip manufacturing.