Provides an account of what is now known about physics at scales of 1013 to 1016 cm. The existence of spin half quarks interacting through colour fields is established fact, as is the structure unifying electromagnetic and weak interaction. In Femtophysics, the author explains the evidence and communicates the essential physics underlying these recent and remarkable developments. The approach throughout is to obtain results by applying trivial algebra to the content of simple and clear physical pictures. Thus, abstract and difficult concepts can be mastered painlessly while maintaining a firm grip on the essentials. The diligent student, therefore, should acquire a comprehensive understanding of the principles underlying present day particle physics.