It controls the amount is usually mechanical and energy flows associated with mechanical switch position, angle and speed. NC data generation depends on the emergence of carrier operations and data in binary form. 1908, perforated metal sheet interchangeable data carriers come; the late 19th century, paper as a data carrier and a control system of auxiliary functions were invented; 1938, Shannon at MIT were fast computing and data transmission, laid the modern computer, including basic computer numerical control system. CNC technology is closely integrated with the machine control developed. In 1952, the first CNC machine tools available, to become the world's industrial machinery and a landmark in the history of the event, to promote the development of automation.

Now, digital technology, also known as computer numerical control technology (CNC, Computerized Numerical Control), which is currently using a computer program to control digital technology. This technique is used by the computer prior to the implementation of the control program stored on the trajectory of the equipment and peripherals operate sequential logic control functions. As a result of the computer numerical control device previously used alternative hardware logic circuit, so that the input operation instruction storage, processing, computation, logic and other various control functions to achieve, can be done by computer software, transmits the generated micro instruction processing servo motor drive means or hydraulic actuators driven equipment running.

Traditional machining is done by hand general machine operation, processing of metal cutting machine tool by hand shake, by eye measurement with calipers and other tools of precision products. Modern industry has already digitized using a computer-controlled machine tools for the job, and CNC machine tools can automatically direct any of the products and components for processing in accordance with pre-programmed technician program. This is what we are talking about CNC machining. CNC machining is widely used in any area of ​​all machining, it is the development trend of mold and important and necessary technical means.