Nowadays on most CNC machines little or no programming is required, however, manual programming of a CNC machine can be beneficial in correcting small errors.
The conventional textual programming requires a manual entry of path conditions, the G functions and the additional functions, called M functions. These were standardized as ISO 66025 for all CNC machines and are common used with the G-code name according to DIN / ISO.
These manual input or programming is completely unnecessary today. Modern CAD / CAM systems replace the textual programming by a graphical, workshop-oriented CNC programming. So, the designer simply draws the desired workpieces within the CAD program that converts this drawing into a finished CNC file. Subsequently, the computer-controlled CNC machine moves as programmed processing the workpiece.
Since it is now even possible to integrate a quality control in the manufacturing process, is no more need for a constant supervision of CNC machines. The tool wear is monitored fully automatically.