This text appeals to readers' intuitive grasp of the wave theory of light, explaining how quantum mechanics arises from the diffraction and interference experiments in the same manner of physical optics. Coherent examples explore the quantum mechanical analog of classical quantities, and the entire work examines the physical meanings of the theory and its applications. Providing a semester's worth of introductory material, this treatment explores quantum mechanics in a balanced, integrated manner. Subjects explored in the introductory chapters were chosen for their mathematical simplicity. Physical applications stressed in later chapters will prepare students for topics they are likely to encounter early in further studies of atomic and nuclear physics.