Major superconducting properties including zero resistance, Meissner effect, sharp phase change, flux quantization, excitation energy gap, Josephson effects are covered and microscopically explained, using quantum statistical mechanical calculations. First treated are the 2D superconductivity and then the quantum Hall effects. Included are exercise-type problems for each section. Readers can grasp the concepts covered in the book by following the worked-through problems. Bibliographies are included in each chapter and a glossary and list of symbols are given in the beginning of the book. The book is based on the materials taught by S. Fujita for several courses in Quantum Theory of Solids, Advanced Topics in Modern Physics, and Quantum Statistical Mechanics.