CNC machining defines several processing methods in industrial production in which CNC machines are used to turn the work piece into the desired shape by mechanically removing excess material (chips). Typical machining methods that fall under the category of CNC machining are CNC turning, CNC milling, CNC grinding and CNC drilling. Generally, the materials to be processed are metals, but other materials such as wood and plastics can be processed by means of cutting. The companies operating in this area typically produce turned and milled parts in small, medium and large series (contract machining). Sample parts (individual pieces) can also be manufactured.