A glyphs directory represents a layer of glyph data in a font. The glyph data files will be in Glyph Interchange Format (GLIF) Version 2 or GLIF 1 (defined in the UFO 2 specification). The directory may contain zero or more GLIF files. It must contain a contents.plist file defining the file name to glyph name mapping even if no GLIF files are present. A layerinfo.plist file may be present defining various properties of the layer.