This book is a comprehensive and unified treatment of modern theoretical and experimental particle physics aimed at beginning graduate students. The emphasis throughout is on presenting underlying physical principles in a simple and intuitive way. In 1983, researchers detected the existence of W and Z bosons and many new results have followed. This is the first graduate-level textbook to deal with the "second generation" of particle physics after 1983. Features of this edition include: A detailed discussion of higher order electroweak effects; an expanded discussion of quark mixing; revised sections on charm and beauty and on jet physics; enlarged treatment of deep inelastic lepton-hadron scattering; detailed treatment of QCD corrections to the simple parton model; and an introduction to the nonperturbative or confinement region of QCD.