The machining surface shape of a milling machine is generally composed of straight lines, arcs, or other curves. Ordinary milling machine operators shall follow the requirements of the drawings. Continuously changing the relative position between the tool and the workpiece, and then matching it with the selected milling cutter speed, the tool can cut and process the workpiece to produce various shapes of workpieces.

CNC machine tool processing is the process of dividing the motion coordinates of the cutting tool and the workpiece into the smallest unit quantity, that is, the minimum displacement. According to the requirements of the workpiece program, the CNC system moves each coordinate by several minimum displacements to achieve relative motion between the tool and the workpiece, in order to complete the machining of the part.