Mathematica supports state-of-the-art splines for use both in graphics and computational applications. Mathematica allows not just cubic splines, but splines of any degree—for curves, surfaces, and in general manifolds of any dimension. Mathematica can not only handle and import splines numerically, but can also represent them as explicit piecewise symbolic functions, fully integrated with all Mathematica's computational functionality.
BezierFunction — create a function representing a Bézier manifold in any dimension
BSplineFunction — create a function representing a B-spline manifold in any dimension
Interpolation — create interpolations using splines and other methods
BezierCurve — 2D or 3D composite Bézier curves of any degree
BSplineCurve — 2D or 3D B-spline (NURB) curves of any degree
BSplineSurface — B-spline (NURB) surfaces of any degree