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Part 3: Terms and definitions



NOTE: These definitions are to explain terms as they relate to their use in the UN/EDIFACT documentation.
This glossary will be extended and improved by the secretariat based on requests and submissions.


Application: a specific function or data processing program.
ASC X12: Standards Committee X12 accredited by the American National Standards Institute (ANSI) and comprised of government and industry members meeting for the purpose of creating national EDI standards for submission to ANSI for subsequent approval and dissemination; and/or for the submission to the UN/ECE for approval and submission of UN/EDIFACT international standards.
ASCII: American Standard Code for Information Interchange. ASCII is a seven bit code with an eighth bit used for parity. The term is used to describe the format for transmission and for storage.
AS/EB: Asian EDIFACT Board.
AZ/EB: Australian/New Zealand EDIFACT Board.


Bureau (WP.4): Office bearers (Chairman and Vice Chairman) of UN/ECE/WP.4 and its Meeting of Experts on Data Elements and Automatic Data Interchange (GE.1) and Meeting of Experts on Procedures and Documentation (GE.2), and WP.4 Secretariat. [UN/EDIFACT Procedures]


CCITT: Comité consultatif international télégraphique et téléphonique (International Telegraph and Telephone Consultative Committee). A group responsible for the establishment of international telecommunications standards.
CEC: Commission of the European Economic Communities. Governing body of the European Community.
CE/EB: Central and Eastern European EDIFACT Board.
CEN: European Committee for Standardization, standardization committee for the European Community.
Character set: a finite set of different characters that is considered complete for a given purpose. [ISO 9735]
(a) a character string used as an abbreviated means of recording or identifying information.
(b) to represent or identify information using a specific symbolic form that can be recognized by a computer. [ISO TC154/SC1]
Component data element: a simple data element which is a subordinate portion of a composite data element and an interchange identified by its position within the composite data element. [ISO 9735]
Component data element separator: a character used to separate component data elements in a composite data element. [ISO 9735]
Composite data element: a data element containing two or more component data elements. [ISO 9735]
Conditional: a statement in a segment or message directory of a condition for the use of a segment, a data element, a composite data element, or a component data element (cf. mandatory). [ISO 9735]


Data: a representation of facts, concepts or instructions in a formalized manner suitable for communication, interpretation or processing by human beings or by automatic means. [ISO 9735]
Data element: a unit of data which, in a certain context, is considered indivisible. [ISO 2382/4] UN/EDIFACT: a unit of data for which the identification, description and value representation have been specified. [ISO 9735]
Data element attribute: a defined characteristic of a data element.
Data element directory: a listing of identified, named and described data element attributes, with specifications as to how the corresponding data element values shall be represented. [ISO 9735]
Data element name: one or more words in a natural language identifying a data element concept. [ISO 9735]
Data element reference number: see data element tag.
Data element requirement designator: see requirement designator.
Data element separator: a character used to separate data elements in a segment. [ISO 9735]
Data element tag: a unique identifier for a data element in a data element directory. [ISO 9735]
Data element value: the specific entry of an identified data element represented as specified in a data element directory.
Data element representation: the format (e.g. numeric, alphabetic, variable length etc.) of a data item.
Data unit: a segment, segment group, composite data element, data element as defined in a directory and its message type specifications.
Directory version: an indication of the issue of a Directory. It includes the last two figures of the year of agreement and a third figure indicating whether it contains UNSMs or TRIAL message types with resp. supporting material.
DISA: Data Interchange Standards Association. Secretariat of the ASC X12 Committee. Also serves as the secretariat for the Pan American EDIFACT Board.
Document: a data carrier and the data recorded on it, that is generally permanent and that can be read by man or machine. [ISO 2382/4]
DRG: Directory Reference Group, the UN group which recommends all changes to the UNTDID for agreement by WP.4.


EB: See EDIFACT Board.
EC: European Community, the twelve member states of the European Economic Community.
ECE: Economic Commission for Europe. See UN/ECE.
EDCD: directory of composite data elements included in UNTDID. [UN/EDIFACT Procedures]
EDCL: directory of code sets associated with coded data elements.
EDED: directory of data elements included in the UNTDID (a subset of the UNTDED).
EDI: see Electronic Data Interchange.
EDIFACT: Electronic Data Interchange for Administration, Commerce and Transport. See UN/EDIFACT.
EDIFACT Board: the advisory and support team for a UN/EDIFACT Rapporteur. See rapporteur advisory and support team.
EDMD: directory of messages included in UNTDID. [UN/EDIFACT Procedures]
EDSD: directory of segments included in the UNTDID.
EFTA: European Free Trade Association, composed of Austria, Finland, Iceland, Norway, Sweden and Switzerland.
Electronic Data Interchange: the computer-to-computer transmission of (business) data in a standard format.
Explicit representation: the technique used to give an absolute identification of the location of a data segment within a message.


Formal trial: a (Status 1) Draft Recommendation phase in UNSM development, agreed by WP.4, before a draft UNSM reaches the status of Recommendation (Status 2). N.B. This does not preclude prior testing. [UN/EDIFACT Procedures]
Framework (message framework): a template containing a sequenced set of all groups/segments which relate to a functional business area (or multi-functional business area) and applying to all messages defined for that area (or areas). [TRADE/WP.4/R.633]
Functional group: one or more messages of the same type headed by a functional group header service segment and ending with a functional group trailer service segment. [UN/EDIFACT Procedures]
Functional group header: the service segment heading and identifying the functional group. [ISO 9735]
Functional group trailer: the service segment ending a functional group. [ISO 9735]
Functional requirement: identification of the business or administrative needs to be met. [UN/EDIFACT Procedures]


GE.1: UN/ECE WP.4 Experts on Data Elements and Automatic Data Interchange, meeting in the framework of WP.4.
GE.2: UN/ECE WP.4 Experts on Procedures and Documentation, meeting in the framework of WP.4.
Generic data element: see qualified data element.
Group of segments: identified, usually repeatable, grouping of segments.


Header section: the portion of the message which precedes the actual body and trailer of the business transaction, and which contains information which relates to the entire message. Synonymous with header area.


Identifier: a character or group of characters used to identify or name an item of data and possibly to indicate certain properties of that data. [ISO 9735]
Implicit representation: the technique whereby the location of a data segment is implied from its relative position within the message.
Interchange: communication between partners in the form of a structured set of messages and service segments starting with an interchange control header and ending with an interchange control trailer. [ISO 9735]
Interchange agreement: document, usually in the form of a user manual, which describes, e.g., level of syntax, messages, legal and security requirements, etc.
ISO: International Organization for Standardization, based in Geneva. It is a federation of national standards organizations.
ISO 7372: ISO Trade Data Elements Directory, identical to sections 1, 2, 3, 4 and 9 of UNTDED.
ISO 9735: International Standard issued by ISO which reproduces the UN/EDIFACT Syntax Rules as agreed by WP.4.
ISO 2382: ISO Data Processing Vocabulary.


JTC/EDI: the Standards Council of Canada Joint Technical Committee on EDI (JTC/EDI) and serves as Canada's representative to ISO.
JRT: Joint Rapporteur Team. Joint meeting of all rapporteur and advisory support teams.




Level: relative hierarchical position of a data segment within a message.


Mandatory: a statement in a segment or message directory which specifies that a segment, a data element, a composite data element or a component data element must be used. [ISO 9735]
Maximum use: specifies the maximum number of occurrences allowed for a data element, composite data element, segment or a loop which maybe repeated.
Message: an ordered series of characters intended to convey information. [ISO 2382/16] UN/EDIFACT: a set of segments in the order specified in a message directory starting with the message header and ending with the message trailer. [ISO 9735] Equivalent to a transaction set.
Message code: a unique six character alphabetic reference identifying a message type.
Message diagram: a graphic representation of the sequence of segments within a message.
Message directory: a listing of identified, named, described and specified message types. (EDMD, TRMD)
Message header: the service segment starting and uniquely identifying a message. [ISO 9735]
Message trailer: the service segment ending a message. [ISO 9735]
Message type: an identified and structured set of data elements covering the requirements for a specified type of transaction, e.g. invoice. [ISO 9735]


National standards body: an organization within a country charged with developing national standards and contributing to international standardization through ISO. [UN/EDIFACT Procedures]
Nested segment: a segment which directly relates to another segment in an identified and structured group of segments covering the requirements for a specific message type. [ISO 9735]


Omission: exclusion in an actual message of one or more units of data which are defined as conditional in a message type specification. [ISO 9735]


PA/EB: Pan American EDIFACT Board. Support and advisory team for the Pan American Rapporteur.
Progressive data transfer: a technique allowing a sender to transfer a series of messages as more data becomes available. The recipient creates, for this purpose, a business file for the eventual linking of all the data. The messages are linked by common referencing.


Qualified data element: a data element whose precise meaning is conveyed by an associated qualifier
Qualified data segment: a data segment whose precise meaning is conveyed by an associated qualifier.
Qualifier: a data element whose value shall be expressed as a code that gives specific meaning to the function of another data element or a segment. [ISO 9735]


Rapporteur (UN/EDIFACT rapporteur): person nominated by his/her government and appointed by UN/ECE/WP.4 to initiate and co- ordinate UN/EDIFACT development work in his/her geographical area of jurisdiction. The nomination must be endorsed by the countries in that area of jurisdiction. [UN/EDIFACT Procedures]
Rapporteur advisory and support team: a body of experts organized in committees providing co-ordinated input and support to the rapporteurs. Their tasks include conformance analysis, message design, maintenance, documentation and promotion. [UN/EDIFACT Procedures]
Receiving Secretariat: the receiving secretariat is the RT secretariat which has received a new message request, change request or code request and which fulfills secretariat duties until a supporting secretariat is assigned by the working group (see supporting secretariat).
Release: a unique sub-issue of a Directory Set within a Version. Releases are used to further define Version publications of the UN/EDIFACT standards. See Version/Release.
Release character: a character used to restore to its original meaning any character used as a syntactical separator. [ISO 9735]
Repeating segment: a segment which may repeat in a message as specified in the relevant message type specification. [ISO 9735]
Requirement designator: specifies whether an element or segment is mandatory or conditional. Also referred to as status.
RT: Rapporteur Team. See rapporteur advisory and support team.


Section control segment: a service segment used to separate header, detail and summary sections of a message where necessary to avoid ambiguities in the message segment content.
Segment: a predefined and identified set of functionally related data elements values which are identified by their sequential positions within the set. A segment starts with a segment tag and ends with a segment terminator. It can be a service segment or a user data segment.
Segment code: a code which uniquely identifies each segment as specified in a segment directory. [ISO 9735]
Segment directory: a listing of identified, named, described and specified segments. [ISO 9735] See EDSD.
Segment name: one or more words in a natural language identifying a data segment concept.
Segment qualifier: see qualifier. Segment table: a table showing the sequential order of segments, their arrangements in segment groups and the status and allowed repetitions of the segments and groups in a message.
Segment tag: a composite data element in which the first component data element contains a code which uniquely identifies a segment as specified in the relevant segment directory. Additional component data elements can be conditionally used to indicate the hierarchical level and nesting relation in a message and the incidence of repetition of the segment. [ISO 9735]
Segment terminator: a syntax character indicating the end of a segment. [ISO 9735]
Separator character: a character used for syntactical separation of data. [ISO 9735] Also known as a delimiter.
Service data element: a data element used in service segments. [ISO 9735]
Service segment: a segment required to service the interchange of user data. [ISO 9735]
Service string advice: a character string at the beginning of an interchange defining syntactically delimiting characters and indicators used in the interchange. [ISO 9735]
Simple data element: a data element containing a single value. [ISO 9735]
Simple segment: a segment which requires no qualification, i.e. whose meaning is fixed and explicit.
Status (1): UN/EDIFACT documents/messages bear an indicator of their development level. They can have the following status:
Draft Document Status 0 (zero)
Draft Recommendation Status 1
Recommendation Status 2
Status (2): indication whether a segment group, segment, composite data element or data element item is mandatory (M) or conditional (C) in the application concerned.
Sub-set: an extract of a message type for use within an industry or application. The extract shall follow the rules for omission of data units and the subset usually indicates only those units needed by the industry or application. See UNSM sub-set.
Summary section: the portion of the message which follows the body of the message and which contains summary information relating to the entire message. Synonymous with summary area.
Supporting Secretariat: the supporting secretariat is the secretariat includes responsibility for submission of their documentation.
Syntax rules: rules governing the structure of an interchange and its functional groups, messages, segments and data elements. [ISO 9735]


Tag: a unique identifier for a segment or data element. [ISO 9735]
TC154: ISO Technical Committee 154 for Documents and Data Elements in Administration, Commerce and Industry.
Technical assessment: the process by which UN/EDIFACT Messages and supporting Directories are evaluated for conformance to syntax, message design and syntax implementation rules. Technical Assessment is performed within the Rapporteur's Teams as part of the agreed UN/EDIFACT Procedures.
Trade Facilitation Organization: a national body co-ordinating or monitoring trade facilitation developments at national level, providing input to UN/ECE/WP.4 and disseminating information on trade facilitation developments, including UN/EDIFACT. [UN/EDIFACT Procedures]
TRADE/WP.4/R....: a document issued by the UN/ECE/WP.4 Secretariat in conjunction with the meetings of UN/ECE/WP.4. Such documents can be obtained from the national Trade Facilitation Organization, or equivalent organization, or the UN/ECE secretariat. [UN/EDIFACT Procedures]
Trade data interchange application protocol (TD-AP): an accepted method for interchange of trade data messages, based on international standards for the presentation and structuring of trade data transfers conveyed by teletransmission.
Trade data log: a collection of trade data transfers that provides a complete historical record of trade data interchanged.
Trade data message: trade data exchanged between parties concerned with the conclusion or performance of a trade transaction.
Trade data transfer: (also referred to as "transfer"); one or more trade data messages sent together as one unit of dispatch which includes heading and terminating data.
Trade transaction: a specific contract for the purchase and sale or supply of goods and/or services and/or other performances between the parties concerned, identified as the transaction to which a trade data message refers.
Trading partners: the sending and/or receiving parties involved in exchanging electronic business messages.
TRIAL Directory: See UN/EDIFACT TRIAL Directory


UNCID: Uniform Rules of Conduct for the Interchange of Trade Data by Teletransmission, developed by the International Chamber of Commerce. [UN/EDIFACT Procedures]
UN/ECE: United Nations Economic Commission of Europe, one of the five regional commissions of the United Nations. It is comprised of North America, Western Europe and Eastern Europe. Headquarters are in Geneva. [UN/EDIFACT Procedures]
UN/ECE WP.4: Working Party on Facilitation of International Trade Procedures, a subsidiary body of UN/ECE Committee on the Development of Trade. WP.4 includes national delegations appointed by governments and international organizations having consultative status with UN or invited by the Secretariat. It is comprised of experts on data elements and automatic data interchange (GE.1) and experts on procedures and documentation (GE.2) which are appointed by their governments or by organizations recognized by UN/ECE.
UN/EDIFACT: United Nations rules for Electronic Data Interchange for Administration, Commerce and Transport. They comprise a set of standards, directories and guidelines for the electronic interchange of structured data, and in particular that related to trade in goods or services, between independent computerized information systems. Recommended within the framework of the United Nations, the rules are approved and published by the UN/ECE in the United Nations Trade Data Interchange Directory (UNTDID) and are maintained under agreed procedures. UNTDID includes:
* the UN/EDIFACT Application Level Syntax Rules (ISO 9735);
* the UN/EDIFACT Message Design Guidelines (MDG);
* the UN/EDIFACT Syntax Implementation Guidelines (SIG);
* the UN/EDIFACT Data Element Directory, EDED (a subset of UNTDED);
* the UN/EDIFACT Code List, EDCL;
* the UN/EDIFACT Composite Data Element Directory, EDCD;
* the UN/EDIFACT Segment Directory, EDSD;
* the UN/EDIFACT United Nations Standard Message Directory (UNSM), EDMD;
* Uniform Rules of Conduct for the Interchange of Trade Data by Teletransmission (UNCID);
* Explanatory material.
UN/EDIFACT TRIAL Directory: a directory including message types and their supporting segments, composite data elements, data elements and codes agreed by WP.4 to be issued for trial.
UN Layout Key (UNLK): A pro-forma document used for indicating spaces reserved for certain statements appearing in international trade documents in an integrated system. [ECE; ISO DP 6422]
UNSM: United Nations Standard Message, an EDIFACT message type approved for international use. A UNSM is a message which:
I. has been registered, published and which is maintained by the United Nations Economic Commission for Europe;
II. has the values contained in the Controlling Agency, Message Type, Message Version Number and Message Release Number fields (the requirements for the use of which are specified in ISO 9735), allocated and controlled by the UN/ECE;
III. always has the code value "UN" in the Controlling Agency field. [UN/EDIFACT Procedures]
UNSM Sub-set: a sub-set of a UNSM is a message which is directly derived from an approved UNSM, has the same function as the UNSM from which it is derived, and which:
I. contains all of the groups and segments defined as having a mandatory status within the message, and the mandatory data elements within them. There shall be no change to the status, order or content of the groups, segments and composite data elements and data elements contained within the segments. (It should be noted, however, that although many UNSMs contain Conditional Groups of segments which may contain one or more mandatory segments, providing the complete conditional group is omitted from the sub-set, this does not break the rule regarding the inclusion of mandatory segments);
II. does not change the status, order or content of the segments, composite data elements and data elements in the conditional segments chosen for use from the UNSM.
III. does not add any segments, composite data elements or data elements to the message;
IV. contains the identical values specified for use in the Message Type, Controlling Agency, Message Version Number and Message Release Number fields, as are specified for the UNSM from which the sub-set is derived. [UN/EDIFACT Procedures]
UNTDED: United Nations Trade Data Elements Directory, part of which constitutes ISO 7372. It includes the standard data elements and associated codes. UNTDED is jointly maintained by the UN Secretariat and ISO. [UN/EDIFACT Procedures]
UNTDID: United Nations Trade Data Interchange Directory. See UN/EDIFACT for documents included in the UNTDID. [UN/EDIFACT Procedures]
User data segment: a segment containing application data. [ISO 9735]


Version number: a number identifying the status of a message type. See Version/release.
Version/release: indication of the periodic issue of a UNTDID or a UN/EDIFACT TRIAL Directory and of their respective sets of message types and their supporting material.


WE/EB: Western European EDIFACT Board.
WP.4: Working Party 4. See UN/ECE/WP.4.


X12: See ASC X12.