Provides an introduction to the structure and function of biomolecules --- especially proteins --- and the physical tools used to investigate them The discussion concentrates on physical tools and properties, emphasizing techniques that are contributing to new developments and avoiding those that are already well established and whose results have already been exploited fully New tools appear regularly - synchrotron radiation, proton radiology, holography, optical tweezers, and muon radiography, for example, have all been used to open new areas of understanding