In geometry the net of a polyhedron is an arrangement of polygons in the plane which can be folded to become the faces of the polyhedron.
Polyhedral nets are a useful aid to the study of polyhedra and solid geometry in general, as they allow for models of polyhedra to be constructed from material such as thin cardboard.
When the Earth is mapped on a polyhedron, its net is a flat world map, e.g. the Dymaxion Map.