Defines the format of the data stream used to interchange documents structured in accordance with ITU-T Rec. T.412 / ISO/IEC 8613-2 and the representation of the constituents which may appear in an interchanged document. The purpose is to facilitate the interchange of documents for either or both of the following purposes: to allow presentation as intended by the originator, to allow processing, such as editing and reformatting. Documents are to be items such as memoranda, letters, invoices, forms and reports, which may include pictures and tabular material. The content elements used within the documents may include graphic characters, raster graphics elements and geometric graphics elements.