The main provisions, concepts and definitions of the theory of metal cutting are set out; phenomena of deformation of the shear layer of metal, phenomena of friction, heat generation and heat removal when cutting metals, purity and accuracy of processing, cutting alloys, geometry and wear of the cutting tool; mechanics of the cutting process. The main factors of the cutting process are considered in relation to the features of turning, planing, drilling, milling, grinding and other types of metal cutting. The main directions of high-speed processing of workpieces on metal-cutting machines are described and methods for determining modes of maximum productivity of various types of processing for serial and mass production are given. The book is intended for students of engineering universities as a teaching aid.