CNC turning is a machining process in which a cutting tool, typically a non-rotary tool bit, is used to remove material from a rotating workpiece to create a desired shape. The workpiece is typically mounted on a spindle, which rotates it, and the cutting tool is moved along different axes to remove material and create the desired shape. CNC stands for “computer numerical control,” which means that the cutting tool is controlled by a computer program rather than a human operator.