This interactive figure will help you visualize surfaces built on curves. You can see different examples by dragging the slider. In each example, a curve is given in the [math]xy[/math]-plane and a surface perpendicular to curve is constructed so that the height of the surface over point [math](x,y)[/math] is [math]y[/math].

[i]Developed for use with Thomas' Calculus, published by Pearson.[/i]