as tool converter and coolant. Numerical control machining has a great advantage over manual machining. For example, the parts produced by numerical control machining are very accurate and repeatable. CNC machining can produce parts with complex shapes that cannot be processed manually. Numerical control machining technology has been widely popularized. Most machining workshops have numerical control machining capability. The most common CNC machining methods in typical machining workshops include numerical control milling, numerical control turning and numerical control EDM line cutting (EDM line cutting). Tools for CNC milling are called CNC milling machines or CNC machining centers. The lathe used for CNC turning is called the CNC turning center. Nc machining G code can be manually programmed, but usually machining workshops use CAM(computer-aided manufacturing) software to automatically read CAD(computer-aided design) files and generate g-code programs to control CNC machine tools.