This Demonstration shows the intersections of planes perpendicular to the axes with plots of quadratic forms, which are paraboloids, hyperbolic paraboloids, ellipsoids, cones, or hyperboloids of one or two sheets.
Curvature and Torsion
Choose among several curves and see the rotation of the Frenet-Serret frame as you move the slider. From this you can perceive the curvature and torsion of the curve. Associated objects (such as the circle of curvature, evolute, and osculating sphere, as well as two views of the Frenet frames) may be displayed.