Lectures on Classical and Quantum Theory of Fields This textbook on classical and quantum theory of fields addresses graduate students starting to specialize in theoretical physics. It provides didactic introductions to the main topics in the theory of fields while taking into account the contemporary view of the subject. The student will find concise explanations of basic notions essential for applications of the theory of fields as well as for frontier research in theoretical physics. One third of the book is devoted to classical fields. Each chapter contains exercises of varying degree of difficulty with hints or solutions plussummaries and worked examples as useful. The textbook is based on lectures delivered to students of theoretical physics at Jagiellonian University. It aims to deliver a unique combination of classical and quantum field theory in one compact course. Both authors work in the Department of Field Theory at the Marian Smoluchowski Institute of Physics Jagiellonian University Cracow. They are experienced academic teachers specialized in theoretical and mathematical physics. Professor Henryk Arodz has published research papers on the Yang Mills fields topological defects and several other topics in field theory and quantum mechanics. Dr. Leszek Hadasz has investigated among other things exactly solvable models with (super )conformal symmetry and strings in non critical dimensions.