The Curve function allows you to draw a four-point mathematically defined Bezier/Spline Curve in the Trace software. The Bezier/Spline Curve is defined by four points: Initial Position (called an Anchor), Two Separate Middle Points (called Handles) which can be moved to alter the shape, and the Terminating Position (called an Anchor) The Convert Arc to Splines process will convert any Arcs to Splines/Curves which are easier to tangify to make cuts smoother.  See: Arc Definition See: Arcs Tool Function See: Splines Definition See: Splines Tool Function See: Convert Arc to Splines Function | 
