The Sinumerik 810D/840D is part of the changeable control WinNC. WinNC allows the user to learn up to nine different, commercially used controls, on a single machine. One of these 9 controls is the 810D/840D. It corresponds in handling and function the particular original control and it can be used on a commercial PC. The user has the possibility to work on the PC as well as on the original control (on the machine) and gets familiar with all aspects of control programming in detail.