The reference book defines the basic physical concepts, summarizes the physical laws and the essence of the phenomena described by them. It reflects all the main sections of classical and modern physics. The mathematical knowledge required to use the reference book does not exceed the amount of material given in the "Reference Book on Mathematics for Engineers and University Students" by I.N. Bronstein and K.A. Semendyaeva. The handbook is designed for engineering and technical workers, students and graduate students of universities and technical colleges, teachers of higher and secondary schools. It can also be used by people interested in physics. 4th edition, revised.