CNC Machining is the process of using CNC machines to work on metals and other materials, referring specifically to the machining done with CNC tools. Computer Numerical Control machines, are programmed and controlled by CNC machining language, typically G-code. This G-code language instructs the machining tool of the CNC machine on the Cartesian position coordinates to adopt, and controls the feed rate and spindle speed of the tool, as well as tool changer, coolant, and other functions. CNC machining has significant advantages over manual machining. For instance, parts produced through CNC machining are highly precise and repeatable; CNC machining can produce complex-shaped parts that manual machining cannot achieve.