Currently, CNC machine tools all use NC program input or transfer from memory and computers to control the cutting process on centers such as milling centers. Therefore, the method of programming NC programs is a crucial step for engineers in factories producing machine parts in the mechanical industry. A specific and clear programming method is needed to facilitate accurate and rapid programming, meeting the demands of modern production and achieving high productivity. This article will focus on providing specific guidance on NC programming for all operators or controllers of CNC milling centers.