👉 A contour is a type of surface that is defined by its boundary, which is the curve traced out by points moving in a closed loop around it. Contour lines are used to represent the shape or structure of a surface and can be drawn on various types of surfaces, such as plane curves, circular arcs, or curved surfaces like cylinders, cones, and spheres. The term "contour" refers to the curve traced out by points moving in a closed loop around it.
