NURBS are the curve and surface representation used for modeling in Alias.

NURBS stands for Non-Uniform Rational B-Splines.

• Non-Uniform refers to the parameterization of the curve. Non-Uniform curves allow, among other things, the presence of multi-knots, which are needed to represent Bezier curves.
• Rational refers to the underlying mathematical representation. This property allows NURBS to represent exact conics (such as parabolic curves, circles, and ellipses) in addition to free-form curves.
• B-splines are piecewise polynomial curves that have a parametric representation.

For more information on NURBS objects, see the following:

• Curves
• Surfaces
• Object properties