| Variable | Description | |
|---|---|---|
| X | Absolute or incremental position of X axis | |
| Y | Absolute or incremental position of Y axis | |
| Z | Absolute or incremental position of Z axis | |
| A | Absolute or incremental position of A axis (rotational axis around X axis) | |
| B | Absolute or incremental position of B axis (rotational axis around Y axis) | |
| C | Absolute or incremental position of C axis (rotational axis around Z axis) | |
| U | Relative axis parallel to X axis |
X absolute position Y absolute position Z absolute position A position (rotary around X) B position (rotary around Y) C position (rotary around Z) U Relative axis parallel to X V Relative axis parallel to Y W Relative axis parallel to Z M code (another "action" register or Machine code(*)) (otherwise referred to as a "Miscellaneous" function") F feed rate S spindle speed N line number R Arc radius or optional word passed to a subprogram/canned cycle P Dwell time or optional word passed to a subprogram/canned cycle T Tool selection I Arc data X axis J Arc data Y axis. K Arc data Z axis, or optional word passed to a subprogram/canned cycle D Cutter diameter/radius offset H Tool length offset