 These factories are considered to be able to run “with the lights off.” Many factories are capable of lights-out production, but few run exclusively lights-out.Typically, in Computer Numerical Control (CNC) machining, workers are necessary to set up tombstones that hold parts to be manufactured and remove completed parts.As the technology necessary for total automation becomes increasingly available, many factories are beginning to use lights-out production between shifts (or as a separate shift) to meet increasing production demand or to save money on labor.