The standard data elements included in this Directory are intended to facilitate interchange of data in international trade. These standard data elements can be used with any method for data interchange, on paper documents as well as with other means of data communication; they can be selected for transmission one by one, or used within a particular system of interchange rules, e.g. the United Nations syntax rules for Electronic Data Interchange For Administration Commerce and Transport (UN/EDIFACT) developed within the ECE and published as International Standard ISO 9735.