Numerical control technology refers to the use of digital instructions composed of numbers, characters and symbols to realize the action control of one or more mechanical equipment. Usually control mechanical quantities such as position, angle and speed, as well as switching quantities related to the flow direction of mechanical energy. The appearance of numerical control depends on the appearance of data carrier and binary data operation. 1908, perforated metal foil interchangeable data carrier came out; At the end of 19, a control system with auxiliary functions was invented with paper as the data carrier. During the period of 1938, Shannon carried out rapid data calculation and transmission at MIT, which laid the foundation for modern computers, including computer numerical control systems. Numerical control technology is closely combined with machine tool control and developed. 1952, the first CNC machine tool came out, which became an epoch-making event in the history of the world machinery industry and promoted the development of automation.
Now, numerical control technology is also called computer numerical control technology. At present, it is a technology to realize digital program control by computer. This technology uses a computer to execute the control function of the equipment according to the pre-stored control program. Because the numerical control device composed of hardware logic circuit is replaced by computer, the realization of various control functions such as storage, processing, operation and logical judgment of input data can be completed by computer software.