As well as outlining and explaining such historic breakthroughs in human understanding of the physical world as Kepler's law of planetary motion and Newton's law of gravitation, Joanne Baker unravels the sometimes baffling complexities of modern scientific theory - from Planck's law to Pauli's exclusion principle and from Schrondinger's cat to string theory. The essays are accompanied by a range of useful editorial features, including biographies of iconic physicists, timelines of related ideas, explanatory diagrams and display quotations.