What is the difference between DNC and CNC?

<img src="http://www.rgbstock.com/cache1pNQEc/users/z/ze/zela/600/mQc197C.jpg"; style="max-width:400px;float:left;padding:10px 10px 10px 0px;border:0px;" alt="" />a dedicated computer <a href="https://www.dictionary.com/browse/control">control</a>; the <a href="https://www.britannica.com/search?query=machine%20tool">machine tool</a> in CNC and <a href="https://www.sedlacek-t.cz/bazar-cnc-stroju/cnc-centrum/">programovatelné řízení</a> in DNC a no: of machines are controlled by a central computer.