This textbook discusses the development of CNC (Computer Numerical Control) machines and the advantages of these machines over the conventional machine tools. Hardware requirements of NC and CNC machines, constructional details of CNC machines, manual part programming and computer-assisted part programming are discussed in the text. A number of examples of part programming for machining different jobs have been included to enable the students and shop-floor engineers to understand the concepts. Special tooling requirements of CNC machines and maintenance aspects have also been discussed.