Surface curvature refers to the way a surface bends or curves in space. It can be described in terms of how much a surface deviates from being flat. For example, a flat table has zero curvature, while a sphere, like a basketball, has positive curvature because it bulges outward. Curvature can be measured using mathematical concepts, such as the Gaussian curvature, which considers how the surface curves in different directions. Surfaces can also have negative curvature, like a saddle, which curves inward in one direction and outward in another. Understanding surface curvature is essential in fields like geometry and physics.