In geometry, a convex curve is a plane curve that has a supporting line through each of its points.Examples of convex curves include the boundaries of convex sets and the graphs of convex functions. Important subclasses of convex curves include the closed convex curves (the boundaries of convex sets), the smooth curves that are convex, and the strictly convex curves, which have the additional property that each supporting line passes through a unique point of the curve. Combinations of these properties have also been considered.