Numerical control, or NC, refers to the use of abstract programming commands to automate machine tools. Machine tools can be controlled manually through levers or mechanically automated through CAD. NC goes a step further and encodes commands on a medium of storage and these commands then ask the machine tools about how they should function. The early NC machines of 40s and 50s were associated with computers, both analog and digital, to create computer numerically controlled machine tools. CNC, ever since its inception, has revolutionized the design process of products.

CAD CAM software programs are now used in the modern CNC machine tools to provide end to end component designing. CAD CAM software programs are used to produce files. These files use a processor to extract commands needed to operate machines. These commands are then used in CNC machines for the purpose of production. The modern manufacturing machine tools use a variety of components for running. CNC helps the combination of all these tools to form a single cell. CNC also uses controllers to move components from one machine to another where the production process involves the use of multiple machines. All these processes are completely automated to produce parts that are designed by CAD CAM software programs.

While NC and then later on CNC worked on its own, it was during the late 1950s that CAD CAM was associated with CNC. This association gave birth to the modern production process involving CAD CAM CNC. With the fall in prices of computers and software programming, using automation in handling machine tools also became more affordable. Low cost CNC machines came into the picture and completely changed the production process. The involvement of humans became lesser with every passing year and consistency and quality in the production process became higher. Through CNC machines, companies started tackling employment cost more effectively while reducing production time rapidly.

The modern inventions in the domain of production technology have made CNC machines all the more powerful. CNC machines have now started using mylar tapes instead of paper tapes, making their functioning more robust. In more highly integrated environments, tapes have now been partially been replaced by LAN, USB drives and floppy drives.

The increased use of CNC has also now necessitated the formation of new CNC standards. G-Code is one such standard that is widely used today. G-Code is the most used language that CNC machines of today use. Another code that was designed for CNC, called STEP-NC, is now being seen as a replacement for G-Code. Further inventions have also allowed manufacturers to use their own conversational methods of programming instead of G-Code. Recently, CNC machines have been programmed to follow logical commands. These logical commands are called macro programming or parametric programming. Similar to BASIC, these programs offer a large degree of variations to be used in them.

With CAD CAM CNC in place, more and more engineering firms and manufacturing units have made a complete turnaround in their production process. CAD CAM CNC has made life easier for the manufacturers while offering quality products to customers in lesser amount of time.