Textbook in PDF format High temperature superconducting theory drew controversy after the discovery of superconductors at close to room temperatures. However, a consistent microscopic theory of HT superconductivity based on bipolaron mechanism leads to a better understanding of microscopic and macroscopic description. By presenting aspects of superconductivity now joined in a strict theory rather than separate models this work is especially useful for graduate students. Better understanding by combining the theory of superconductivity with that of bipolarons. Explaining numerous experiments on the thermodynamic, spectroscopic and transport characteristics. Problems and solutions for a successful exam preparation