A programmed tool motion creates a pattern, contour or a pocket that can be rotated about a defined point by specified angle. With this control feature, there are many opportunities to make the programming process much more flexible and equally efficient. This very powerful programming feature, usually a special control option, is called the Coordinate System Rotation, or just Coordinate Rotation.
In order to shape metal by machine tools, the cutting tool should move in contact with the workpiece at certain specific points, while the workpiece or cutting tool is rotating.Coordinate system is required to define the movement on the machine.