Creo Interactive Surface Design (Style) > Curves > Understanding Curves > Point Types
  
Point Types
In Style you can create and edit curves in two modes:
Interpolation point editing
Control point editing
Interpolation Points
By default, the interpolation points of a curve are displayed while you create or edit the curve. You can edit the curve by clicking and dragging the points that actually lie on the curve.
Editing Control Points
Click the command on the Curve and Curve Edit tabs to display a curve's control points. You can edit the curve by clicking and dragging these points. Only the first and last control points on a curve can be soft points.