Provides the foundation for understanding the subject of lasers. The topics included in this book are various experiments that led to the foundation of quantum mechanics, concepts of atomic and molecular spectra. Basic concepts of lasers, solid, liquid and gas lasers, Q-switching and mode locking are described.The applications of laser to material processing, medicine and surgery, holography, optical communication, Lidar, military, meteorology, isotope separation, nuclear fusion are discussed.communication, Lidar, military, meteorology, isotope separation, nuclear fusion are discussed.Table of Contentso Prefaceo Foundation of Quantum Mechanicso Concepts of Atomic and Molecular Spectrao Introductions to Laserso Gas Laserso Solid State Laserso Liquid Laserso Laser Applicationso Selected Bibliographyo Subject Index.