This book undertakes the unusual task of correcting and proposing supplements to the Landau and Lifshitz's highly celebrated textbook titled: The Classical Theory of Fields 1, which has been extraordinarily influential. Its first edition was published in 1939, and new editions in many languages continue to be published. Furthermore, it is still cited in scientific works several hundred times each year. The Classical Electrodynamic Part of Landau and Lifshitz's Textbook The Classical Theory of Fields is rigorously analyzed. The need for corrections is proved. The distinction between bound fields and radiation fields is stipulated. Apparent paradoxes, like the "hidden momentum" concept and the 4/3 factor of the Lorentz transformation of the electromagnetic fields' momentum of a charged particle are explained. Inherent contradictions of of the gauge transformations are proved. In particular, it is proved that the apparent gauge invariance of the QED Lagrangian density does not hold because of its inherent mathematical inconsistencies. This analysis clarifies the long debate concerning the meaning of the electromagnetic 4-potential and its gauge transformations. A regular magnetic monopole theory is outlined, and the systematic failure of the quest for Dirac monopoles is proved.