When the CNC system is activated, the required cuts are programmed into the software and the corresponding tools and machinery are instructed, which perform the specified dimensional tasks, much like a robot.
In CNC programming, code generators in digital systems often assume that the mechanism is flawless, although there is a possibility of error, even more so when the CNC machine is instructed to cut in multiple directions at the same time. The placement of the tool in the CNC is outlined by a series of inputs called a part program.
For CNC machines, programs are entered via punched cards. In contrast, programs for CNC machines are entered into the computer via a keypad. CNC programming remains in the computer's memory. The code itself is written and edited by programmers. Therefore, the CNC system provides a wider range of computing capabilities. Most importantly, CNC systems are by no means static, as newer tips can be added to pre-existing programs by modifying the code.