Oberfläche

Oberfläche is a German noun meaning surface. It denotes the boundary or outer skin of a three-dimensional object, and by extension the interface between different media. In mathematics the term designates a two-dimensional manifold embedded in three-dimensional space. Surfaces can be flat or curved, finite or infinite, smooth or jagged, and may be open with an edge or closed without one.

In geometry and topology, a surface is studied through representations such as parametric forms r(u, v) and implicit equations F(x, y, z) = 0. Key properties include curvature measures like Gaussian curvature and mean curvature, and topological invariants such as genus. Examples range from the plane and sphere to the torus. In computer graphics surfaces are often approximated by meshes, while analytic methods describe them with equations and differential geometry.

In science and engineering, Oberflächen affect adhesion, friction, wettability, corrosion, and catalytic activity. Surface roughness and texture influence mechanical performance and chemical reactivity, and are assessed by profilometry, atomic force microscopy, or scanning electron microscopy. In information technology, the term also appears in reference to the user interface of a system—the Oberfläche that users interact with, including layout, controls, and feedback, which are central to usability and accessibility.