The defining feature of Computer Numerical Control (CNC) machines is the level of their accuracy. They can also achieve high performance for very specific machining operations or program.
CNC is a long-established technology for automated machining. The first machine was introduced by John T Parsons an engineer in the 1950s, not long after, the first robot was built. Since then, the two technologies have developed together.
The CNC machine is either a movable tool or a movable jig or both. The control of the tool orientation is sometimes possible. The axis that the machine rotates in are precisely controlled by a computer, which allows a very accurate material removal compared to machining by hand.