A Spline is a flexible line or curve. Splines can be used for modeling, as motion paths for animation, and as adjustment controls in the graph editor. You may be familiar with splines from programs like Adobe Illustrator, or Photoshop. Splines are resolution independent; they are infinitely smooth. Cinema 4D offers the following spline types: Bezier, cubic, B-spline, Akima, in addition to many spline-based 2D primitive shapes.