ISO/IEC 9541 specifies the architecture of font resources, as well as the formats for font interchange among information processing systems. ISO/IEC 9541 also specifies the architecture and formats that can be used to construct font references in general electronic document interchange.

ISO/IEC 9541-3:2012 specifies the architecture and interchange formats of glyph shape representations.

Font resources represented using the architecture and interchange formats defined in ISO/IEC 9541-1 and ISO/IEC 9541-2 are used in various document processing environments in which the RELAX NG (ISO/IEC 19757-2) parsing algorithm is recognized. The encoding of font resource information as defined in ISO/IEC 9541-3:2012 is specified in RELAX NG representation for consistent generation of font resources for use in these processing environments.