Surface (mathematics)

In mathematics, a surface is a generalization of a plane. Unlike a plane, it need not be flat – that is, its curvature need not be zero. This is analogous to a curve generalizing a straight line. There are many more-precise definitions, depending on the context and the mathematical tools used to analyze the surface.

A sphere is the surface of a solid ball, here having radius r

The mathematical concept idealizes what is meant by surface in science, computer graphics, and common language.