A document drawn up in accordance with the procedures and by the bodies specified in the laws and regulations on standardisation, summarising technical requirements of all kinds for a particular product or activity. De facto standards correspond to the implementation of standards based on the success of a solution provided, for example, by a manufacturer. Standards proposed by public bodies are often recognised as de facto standards, which then acquire universal status. – There are different types of standards: – specification (definition of a product); – analysis methods; – security; – quality (ISO 9000); – information processing; – UN-EDIFACT, STEP, SGML, – EDIGEO. – For EDI, EDIFACT uses a « set of standards » consisting of a vocabulary, syntax, standard segments and standard messages. Examples of standards: – ISO 646: character sets for interchange; – ISO 6422: United Nations Framework for Trade Documents; – ISO 7372: UN /TDED, Trade Data Element Directory; – ISO 8571: Information processing open systems interconnection – File Transfer, Access and Management (FTAM). This is a protocol for file transfer; – ISO 9735: EDIFACT application level syntax rules; – CCITT X.400: recommendations, messaging system, architecture. (See in contrast to standard).