Polygon Side textures render white on the front face and black on the back face of a polygon. This is useful for back face culling by putting the Texture into the Opacity channel; creating double-sided MaterialsA set of attributes or parameters that describe surface characteristics. by placing it into a Mix material; and mixing TexturesTextures are used to add details to a surface. Textures can be procedural or imported raster files. by placing it into a Mix texture.
Figure 1: RGB Color nodes add different colors on the front and back sides of polygons