ISO/IEC 11179-1:2015

Information technology - Metadata registries (MDR) - Part 1: Framework

ISO/IEC 11179-1:2015 provides the means for understanding and associating the individual parts of ISO/IEC 11179 and is the foundation for a conceptual understanding of metadata and metadata registries. ISO/IEC 11179-1:2015 is applicable to the formulation of data representations, concepts, meanings and relationships to be shared among people and machines, independent of the organization that produces the data. It is not applicable to the physical representation of data as bits and bytes at the machine level. In this part of ISO/IEC 11179-1:2015 (and all other parts), metadata refers to descriptions of data. It does not contain a general treatment of metadata.

Technologies de l'information — Registres de métadonnées (RM) — Partie 1: Cadre de référence

General Information

• Status: Withdrawn
• Publication Date: 14-Dec-2015
• ICS: 35.040 - Information coding
• ICS: 35.040.50 - Automatic identification and data capture techniques
• Technical Committee: ISO/IEC JTC 1/SC 32 - Data management and interchange
• Drafting Committee: ISO/IEC JTC 1/SC 32/WG 2 - MetaData
• Current Stage: 9599 - Withdrawal of International Standard
• Start Date: 16-Jan-2023
• Completion Date: 30-Oct-2025

Relations

• Revised: ISO/IEC 11179-1:2023 - Information technology - Metadata registries (MDR) - Part 1: Framework
• Effective Date: 23-Apr-2020
• Revises: ISO/IEC 11179-1:2004 - Information technology - Metadata registries (MDR) - Part 1: Framework
• Effective Date: 10-May-2012

Standards Content (Sample)

INTERNATIONAL ISO/IEC
STANDARD 11179-1
Third edition
2015-12-15
Information technology — Metadata
registries (MDR) —
Part 1:
Framework
Technologies de l’information — Registres de métadonnées (RM) —
Partie 1: Cadre de référence
Reference number
©
ISO/IEC 2015
© ISO/IEC 2015, Published in Switzerland
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form
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ii © ISO/IEC 2015 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms, definitions and abbreviations . 1
3.1 Definitions of modelling constructs . 1
3.2 General terms used in this part of ISO/IEC 11179. 2
3.3 Alphabetical list of terms used in the metamodel . 4
3.4 Specific terms used in ISO/IEC 11179-6 . 8
3.5 Specific terms used in this part of ISO/IEC 11179 . 9
4 Theory of terminology . 9
5 Metadata . 9
5.1 General . 9
5.2 Concepts .10
5.2.1 General.10
5.2.2 Management .10
5.3 Fundamental model of data elements .10
5.4 Data elements in data management and interchange .12
5.5 Fundamental model of value domains .12
5.6 Fundamental model of concept systems .15
6 Metadata registries .16
6.1 General .16
6.2 Overview model for an ISO/IEC 11179 MDR.17
6.3 Fundamentals of registration .18
7 Overview of ISO/IEC 11179, Parts 1–6 .19
7.1 Part 1 .19
7.2 Part 2 .19
7.3 Part 3 .19
7.4 Part 4 .20
7.5 Part 5 .20
7.6 Part 6 .20
7.7 Basic principles for applying ISO/IEC 11179, Parts 1–6 .21
8 Conformance .21
Bibliography .22
© ISO/IEC 2015 – All rights reserved iii

Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are
members of ISO or IEC participate in the development of International Standards through technical
committees established by the respective organization to deal with particular fields of technical
activity. ISO and IEC technical committees collaborate in fields of mutual interest. Other international
organizations, governmental and non-governmental, in liaison with ISO and IEC, also take part in the
work. In the field of information technology, ISO and IEC have established a joint technical committee,
ISO/IEC JTC 1.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for
the different types of document should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject
of patent rights. ISO and IEC shall not be held responsible for identifying any or all such patent
rights. Details of any patent rights identified during the development of the document will be in the
Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the meaning of ISO specific terms and expressions related to conformity
assessment, as well as information about ISO’s adherence to the WTO principles in the Technical
Barriers to Trade (TBT) see the following URL: Foreword - Supplementary information
The committee responsible for this document is ISO/IEC JTC1, Information technology, SC32, Data
management and interchange.
This third edition of ISO 11179-1 cancels and replaces ISO 11179-1:2004, which has been technically
revised.
ISO/IEC 11179 consists of the following parts, under the general title Information technology —
Metadata registries (MDR):
— Part 1: Framework
— Part 2: Classification
— Part 3: Registry metamodel and basic attributes
— Part 4: Formulation of data definitions
— Part 5: Naming principles
— Part 6: Registration
iv © ISO/IEC 2015 – All rights reserved

Introduction
ISO/IEC 11179 addresses the semantics of data, the representation of data and the registration of
the descriptions of that data. It is through these descriptions that an accurate understanding of the
semantics and a useful depiction of the data are found.
The purposes of ISO/IEC 11179 is to promote the following:
— standard description of data;
— common understanding of data across organizational elements and between organizations;
— re-use and standardization of data over time, space, and applications;
— harmonization and standardization of data within an organization and across organizations;
— management of the components of descriptions of data;
— re-use of the components of descriptions of data.
Each part of ISO/IEC 11179 is devoted to addressing a different aspect of these needs:
— Part 1: Framework – Contains an overview of the Standard and describes the basic concepts;
— Part 2: Classification – Describes how to manage a classification scheme in a metadata registry;
— Part 3: Registry metamodel and basic attributes – Provides the conceptual model, including the basic
attributes and relationships, for a metadata registry;
— Part 4: Formulation of data definitions – Gives rules and guidelines for forming quality definitions for
data elements and their components;
— Part 5: Naming principles – Describes how to form conventions for naming data elements and
their components;
— Part 6: Registration – Specifies the roles and requirements for the registration process in an
ISO/IEC 11179 metadata registry.
Generally, descriptive data are known as metadata. Metadata can describe books, phone calls, data, etc.
ISO/IEC 11179 focuses upon metadata that describes data.
NOTE In ISO/IEC 11179 (all parts), metadata refers to descriptions of data. It does not contain a general
treatment of metadata.
A metadata registry (MDR) is a database of metadata. Registration is one possible function of that
database. Registration accomplishes three main goals: identification, provenance, and monitoring
quality. Identification is accomplished by assigning a unique identifier (within the registry) to each
object registered there. Provenance addresses the source of the metadata and the object described.
Monitoring quality ensures that the metadata does the job it is designed to do.
An MDR may contain the semantics of data. An understanding of data is fundamental to their design,
harmonization, standardization, use, re-use and interchange. The underlying model for an MDR is
designed to capture all the basic components of the semantics of data, independent of any application or
subject matter area.
MDRs, typically, are organized so that those designing applications can ascertain whether a suitable
object described in the MDR already exists. Where it is established that a new object is essential, its
derivation from an existing description with appropriate modifications is encouraged, thus avoiding
unnecessary variations in the way similar objects are described. Registration will also allow two or
more administered items describing identical objects to be identified, and more importantly, it will
help to identify situations where similar or identical names are in use for administered items that are
significantly different in one or more respects.
© ISO/IEC 2015 – All rights reserved v

In ISO/IEC 11179 the basic container for data is called a data element. It may exist purely as an
abstraction or exist in some application system. In either case, the description of a data element
is the same in ISO/IEC 11179. Data element descriptions have both semantic and representational
components. The semantics are further divided into contextual and symbolic types.
The contextual semantics are described by the data element concept (DEC). The DEC describes the
kind of objects for which data are collected and the particular characteristic of those objects being
measured. The symbolic semantics are described by the conceptual domain (CD). A CD is a set of
concepts, not necessarily finite, where the concepts represent the meaning of the permissible values in
a value domain. A value domain contains the allowed values for a data element.
The names, definitions, datatype and related attributes that are associated with the description of an
object in an MDR give that object meaning. The depth of this meaning is limited, because names and
definitions convey limited information about the object. The relationships object descriptions have
with semantically related object descriptions in a registry provide additional information, but this
additional information is dependent on how many semantically related object descriptions there are.
This third edition of ISO/IEC 11179-1 introduces concepts and concept systems in the description of the
semantics of data. Object classes, properties, DECs, value meanings and CDs are concepts. Therefore,
they have definitions and may be designated by names or codes. They may also be organized through
the use of relations among them into concept systems. A classification scheme is a concept system that
is used for classifying some objects and classification of an object adds meaning to that object.
Features needed for formal reasoning are also new to this third edition of ISO/IEC 11179-1. Applying
the rules of some form of formal logic (1st order logic, predicate calculus, description logic, etc.) may
add additional abilities to query and reason with concept systems. Ontologies are concept systems that
allow the application of formal logic and this edition provides for their use.
The representational component is about the permitted values a data element may use. Each such
permissible value is a designation of one of the concepts in the CD. The set of these permissible values is
called a value domain (VD). A VD specifies all the values that are allowed either through an enumeration,
a rule, or a combination of these. The computational model the values follow is given by their datatype.
The semantic and representational components are described through attributes contained in the
conceptual model of a metadata registry as specified in ISO/IEC 11179-3. A metadata registry that
conforms to ISO/IEC 11179 can describe a wide variety of data. In fact, the attributes described in
ISO/IEC 11179-3 are data elements, and they can be registered in an ISO/IEC 11179 metadata registry.
Moreover, any set of descriptors or metadata attributes may be interpreted as data elements and
registered in the metadata registry.
There are two main consequences to this:
— the metadata registry can describe itself;
— metadata layers or levels are not defined in ISO/IEC 11179.
As a result, ISO/IEC 11179 is a general description framework for data of any kind, in any organization
and for any purpose. ISO/IEC 11179 does not address other data management needs, such as data
models, application specifications, programming code, program plans, business plans and business
policies. These need to be addressed elsewhere.
The increased use of data processing and electronic data interchange heavily relies on accurate, reliable,
controllable and verifiable data recorded in databases. One of the prerequisites for a correct and proper
use and interpretation of data is that both users and owners of data have a common understanding
of the meaning and descriptive characteristics (e.g., representation) of that data, guaranteed by the
definition of several basic attributes.
The basic attributes specified are applicable for the definition and specification of the contents of data
dictionaries and interchanging or referencing among various collections of administered items. The
vi © ISO/IEC 2015 – All rights reserved

“basic” in basic attributes means that the attributes are commonly needed in specifying administered
items completely enough to ensure that they will be applicable for a variety of functions, such as:
— design of information processing systems,
— retrieval of data from databases,
— design of messages for data interchange,
— maintenance of metadata registries,
— data management,
— dictionary design,
— dictionary control,
— use of information processing systems.
Basic also implies that they are independent of any:
— application environment,
— function of an object described by an administered item,
— level of abstraction,
— grouping of administered items,
— method for designing information processing systems or data interchange messages,
— MDR system.
Basic does not imply that all attributes specified in ISO/IEC 11179-3 are required in all cases. Distinction
is made between those attributes that are mandatory, conditional, or optional.
© ISO/IEC 2015 – All rights reserved vii

INTERNATIONAL STANDARD ISO/IEC 11179-1:2015(E)
Information technology — Metadata registries (MDR) —
Part 1:
Framework
1 Scope
This part of ISO/IEC 11179 provides the means for understanding and associating the individual parts of
ISO/IEC 11179 and is the foundation for a conceptual understanding of metadata and metadata registries.
This part of ISO/IEC 11179 is applicable to the formulation of data representations, concepts, meanings
and relationships to be shared among people and machines, independent of the organization that
produces the data. It is not applicable to the physical representation of data as bits and bytes at the
machine level.
In this part of ISO/IEC 11179 (and all other parts), metadata refers to descriptions of data. It does not
contain a general treatment of metadata.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
ISO 704:2009, Terminology work — Principles and methods
ISO 1087-1:2000, Terminology work — Vocabulary — Part 1: Theory and application
ISO/IEC 11179 (all parts), Information technology — Metadata registries (MDR)
3 Terms, definitions and abbreviations
For the purposes of this document, the following terms, abbreviations and definitions apply.
3.1 Definitions of modelling constructs
3.1.1
attribute
characteristic (3.2.2) of an object (3.2.22) or set of objects
3.1.2
class
description of a set of objects (3.2.22) that share the same attributes (3.1.1), operations, methods,
relationships (3.1.4) and semantics
[SOURCE: ISO/IEC 19505-2:2012, 7.3.7 modified]
3.1.3
identifier
sequence of characters, capable of uniquely identifying that with which it is
associated, within a specified context (3.3.7)
Note 1 to entry: A name should not be used as an identifier because it is not linguistically neutral.
© ISO/IEC 2015 – All rights reserved 1

Note 2 to entry: It is possible to define an identifier from the point of view of terminology as defined in ISO 1087-1
and described in ISO 704, as follows: representation of an object by a sign which denotes it, and is intended for
dereferencing that object. Note the parallel with the definition of designation, except this applies to any object
rather than just for concepts.
3.1.4
relationship
connection among model elements
[SOURCE: ISO/IEC 19505-2:2012, 7.3.47 modified]
3.2 General terms used in this part of ISO/IEC 11179
3.2.1
basic attribute
attribute (3.1.1) of a metadata item (3.2.17) commonly needed in its specification
3.2.2
characteristic
abstraction of a property of an object (3.2.22) or of a set of objects
[SOURCE: ISO 1087-1:2000, 3.2.4]
Note 1 to entry: Characteristics are used for describing concepts.
3.2.3
concept
unit of knowledge created by a unique combination of characteristics (3.2.2)
[SOURCE: ISO 1087-1:2000, 3.2.1]
3.2.4
concept system
set of concepts (3.2.3) structured according to the relations among them
[SOURCE: ISO 1087-1:2000, 3.2.11]
3.2.5
conceptual data model
conceptual model
data model (3.2.7) that represents an abstract view of the real world
Note 1 to entry: A conceptual model represents the human understanding of a system.
3.2.6
data
reinterpretable representation of information in a formalized manner suitable for communication,
interpretation or processing
[SOURCE: ISO 2382-1:2015, 2121272 — Notes to entry modified]
Note 1 to entry: Data can be processed by humans or by automatic means.
Note 2 to entry: Data may also be described using the terminological notions defined in ISO 1087-1:2000 and
the computational notions defined in ISO/IEC 11404:2007. A datum is a designation of a concept with a notion of
equality defined for that concept.
3.2.7
data model
graphical and/or lexical representation of data (3.2.6), specifying their properties, structure, and inter-
relationships
2 © ISO/IEC 2015 – All rights reserved

3.2.8
definition
representation of a concept (3.2.3) by a descriptive statement which serves to differentiate it from
related concepts
[SOURCE: ISO 1087-1:2000, 3.3.1]
3.2.9
designation
representation of a concept (3.2.3) by a sign which denotes it
[SOURCE: ISO 1087-1:2000, 3.4.1]
3.2.10
entity
any concrete or abstract thing that exists, did exist, or might exist, including associations among these
things
Note 1 to entry: An entity exists whether data about it are available or not.
EXAMPLE A person, object, event, idea, process, etc.
3.2.11
essential characteristic
characteristic (3.2.2) which is indispensable to understanding a concept (3.2.3)
[SOURCE: ISO 1087-1:2000, 3.2.6]
3.2.12
extension
totality of objects (3.2.22) to which a concept (3.2.3) corresponds
[SOURCE: ISO 1087-1:2000, 3.2.8]
Note 1 to entry: This term has a different meaning in ISO/IEC 11179-3.
3.2.13
general concept
concept (3.2.3) which corresponds to two or more objects (3.2.22), which form a group by reason of
common properties
[SOURCE: ISO 1087-1:2000, 3.2.3]
Note 1 to entry: Examples of general concepts are ‘planet’, ‘tower’.
3.2.14
individual concept
concept (3.2.3) which corresponds to only one object (3.2.22)
[SOURCE: ISO 1087-1:2000, 3.2.2]
Note 1 to entry: Examples of individual concepts are: ‘Saturn’, ‘the Eiffel Tower’.
3.2.15
intension
set of characteristics (3.2.2) which makes up the concept (3.2.3)
[SOURCE: ISO 1087-1:2000, 3.2.9]
3.2.16
metadata
data (3.2.6) that defines and describes other data
© ISO/IEC 2015 – All rights reserved 3

3.2.17
metadata item
instance of a metadata object (3.2.18)
3.2.18
metadata object
object type defined by a metamodel (3.2.20)
3.2.19
metadata registry
MDR
information system for registering metadata (3.2.16)
3.2.20
metamodel
data model (3.2.7) that specifies one or more other models, such as data models, process models,
ontologies, etc
3.2.21
name
designation (3.2.9) of an object (3.2.22) by a linguistic expression
3.2.22
object
anything perceivable or conceivable
[SOURCE: ISO 1087-1:2000, 3.1.1]
Note 1 to entry: Objects may also be material (e.g., an engine, a sheet of paper, a diamond), immaterial (e.g., a
conversion ratio, a project plan), or imagined (e.g., a unicorn).
3.2.23
registry item
metadata item (3.2.17) recorded in a metadata registry (3.2.19)
3.2.24
registry metamodel
metamodel (3.2.20) specifying a metadata registry (3.2.19)
3.2.25
terminological system
concept system (3.2.4) with designations (3.2.9) for each concept (3.2.3)
3.3 Alphabetical list of terms used in the metamodel
3.3.1
administered item
registry item (3.2.23) for which administrative information (3.3.2) is recorded
Note 1 to entry: This entry is defined more generally than it is in ISO/IEC 11179-3.
3.3.2
administrative information
information about the administration of an item in a metadata registry (3.2.19)
EXAMPLE creation date, last change date, origin, change description, explanatory comment
4 © ISO/IEC 2015 – All rights reserved

3.3.3
administrative status
designation (3.2.9) of the status in the administrative process of a registration authority (3.3.25) for
handling registration requests
Note 1 to entry: The values and associated meanings of “administrative status” are determined by each
registration authority. C.f. registration status.
3.3.4
classification scheme
descriptive information for an arrangement or division of objects (3.2.22) into groups based on criteria
such as characteristics (3.2.2), which the objects have in common
Note 1 to entry: A classification scheme is a concept system used for classifying some objects.
EXAMPLE Origin, composition, structure, application, function, etc.
3.3.5
classification scheme item
CSI
item of content in a classification scheme (3.3.4)
Note 1 to entry: This may be a node in a taxonomy or ontology, a term in a thesaurus, etc.
3.3.6
conceptual domain
CD
concept (3.2.3) whose meaning is expressed as an enumerated set and/or a description of subordinate
concepts, which are value meanings (3.3.32)
Note 1 to entry: This definition is more general than the one specified in ISO/IEC 11179-3.
3.3.7
context
circumstance, purpose, and perspective under which an object (3.2.22) is defined or used
Note 1 to entry: The definition is not the same as in 11179–3. The term is used in this part of ISO/IEC 11179 as
defined here.
3.3.8
data element
DE
unit of data (3.2.6) that is considered in context (3.3.7) to be indivisible
[SOURCE: ISO/IEC 15944-1:2011, 3.16]
Note 1 to entry: The definition states that a data element is “indivisible” in some context. This means it is possible
that a data element considered indivisible in one context (e.g., telephone number) may be divisible in another
context (e.g., country code, area code, local number).
3.3.9
data element concept
DEC
concept (3.2.3) that is an association of a property (3.3.21) with an object class (3.3.18)
Note 1 to entry: A data element concept is implicitly associated with both the property and the object class whose
combination it expresses.
Note 2 to entry: A data element concept may also be associated with zero or more conceptual domains each of
which expresses its value meanings.
Note 3 to entry: A data element concept may also be associated with zero or more data elements each of which
provides representation for the data element concept via its associated value domain.
© ISO/IEC 2015 – All rights reserved 5

3.3.10
datatype
set of distinct values, characterized by properties of those values and by operations on those values
[SOURCE: ISO/IEC 11404:2007, 4.11]
3.3.11
described conceptual domain
conceptual domain (3.3.6) that is specified by a description or specification, such as a rule, a procedure,
or a range (i.e., interval)
3.3.12
described conceptual domain description
description or specification of a rule, reference, or range for a set of all value meanings (3.3.32) for the
conceptual domain (3.3.6)
3.3.13
described value domain
value domain (3.3.31) that is specified by a description or specification, such as a rule, a procedure, or a
range (i.e., interval)
3.3.14
described value domain description
description or specification of a rule, reference, or range for a set of all permissible values (3.3.20) for the
value domain (3.3.31)
3.3.15
dimensionality
set of equivalent units of measure (3.3.29)
Note 1 to entry: Equivalence between two units of measure is determined by the existence of a quantity
preserving one-to-one correspondence between values measured in one unit of measure and values measured in
the other unit of measure, independent of context, and where characterizing operations are the same.
Note 2 to entry: The equivalence defined here forms an equivalence relation on the set of all units of measure. Each
equivalence class corresponds to a dimensionality. The units of measure “temperature in degrees Fahrenheit”
and “temperature in degrees Celsius” have the same dimensionality, because:
a) given a value measured in degrees Fahrenheit there is a value measured in degrees Celsius with the same
quantity, and vice-versa, by the well-known correspondences °C = (5/9)*(°F - 32) and °F = (9/5)*(°C) + 32.
b) the same operations can be performed on both values.
Note 3 to entry: The units of measure “temperature in degrees Celsius” and “temperature in degrees Kelvin” do
not belong to the same dimensionality. Even though it is easy to convert quantities from one unit of measure to
the other (°C = °K − 273.15 and °K = °C + 273.15), the characterizing operations in Kelvin include taking ratios,
whereas this is not the case for Celsius. For instance, 20° K is twice as warm as 10° K, but 20° C is not twice as
warm as 10° C.
Note 4 to entry: Units of measure are not limited to physical categories. Examples of physical categories are: linear
measure, area, volume, mass, velocity, time duration, and temperature. Examples of non-physical categories are:
currency, quality indicator, colour intensity
Note 5 to entry: Quantities may be grouped together into categories of quantities which are mutually comparable.
Lengths, diameters, distances, heights, wavelengths and so on would constitute such a category. Mutually
comparable quantities have the same dimensionality. ISO 80000-1 calls these “quantities of the same kind”.
Note 6 to entry: ISO 80000-1 specifies physical dimensions (e.g., length, mass, velocity). This part of ISO/IEC 11179
also permits non-physical dimensions (e.g., value dimensions such as: currency, quality indicator). The present
concept of dimensionality equates to what ISO 80000-1 calls Dimensional Product, rather than to Dimension.
6 © ISO/IEC 2015 – All rights reserved

3.3.16
enumerated conceptual domain
conceptual domain (3.3.6) that is specified by a list of all its value meanings (3.3.32)
Note 1 to entry: No ordering of the value meanings is implied.
3.3.17
enumerated value domain
value domain (3.3.31) that is specified by a list of all its permissible values (3.3.20)
Note 1 to entry: No ordering of the permissible values is implied.
3.3.18
object class
set of ideas, abstractions, or things in the real world that are identified with explicit boundaries and
meaning and whose properties and behaviour follow the same rules
3.3.19
organization
unique framework of authority within which a person or persons act, or are designated to act,
towards some purpose
[SOURCE: ISO/IEC 6523-1:1998, 3.1]
3.3.20
permissible value
designation (3.2.9) of a value meaning (3.3.32)
Note 1 to entry: A permissible value may be associated with one or more enumerated value domains.
Note 2 to entry: As a designation, the value is the sign and the value meaning is the concept.
3.3.21
property
characteristic (3.2.2) common to all members of an object class (3.3.18)
3.3.22
registrar
representative of a registration authority (3.3.25)
3.3.23
registration
inclusion of an item in a registry
3.3.24
registration
inclusion of a metadata item (3.2.17) in a metadata registry (3.2.19)
3.3.25
registration authority
RA
organization (3.3.19) responsible for maintaining a register
3.3.26
registration authority identifier
RA identifier
identifier (3.1.3) assigned to a registration authority (3.3.25)
3.3.27
registration status
designation (3.2.9) of the status in the registration life-cycle of an administered item (3.3.1)
© ISO/IEC 2015 – All rights reserved 7

3.3.28
representation class
classification of types of representations
3.3.29
unit of measure
actual units in which the associated values (3.3.30) are measured
Note 1 to entry: The dimensionality of the associated conceptual domain must be appropriate for the specified
unit of measure.
3.3.30
value
sign, used to represent data (3.2.6)
Note 1 to entry: A value is a sign as used in ISO 1087:2000 and ISO 704:2009.
Note 2 to entry: A value may be a character string, bitmap, or some other symbol.
Note 3 to entry: This definition is more general than the one specified in ISO/IEC 11179-3.
3.3.31
value domain
VD
set of permissible values (3.3.20)
Note 1 to entry: The permissible values in a value domain may either be enumerated or expressed via a description.
3.3.32
value meaning
property
Note 1 to entry: ISO 704 and ISO/IEC 11179 use the term property to mean different ideas.
Note 2 to entry: This definition is more general than the one specified in ISO/IEC 11179-3.
3.3.33
version
unique version identifier (3.1.3) of the administered item (3.3.1)
3.4 Specific terms used in ISO/IEC 11179-6
3.4.1
stewardship
responsibility for the maintenance of administrative information (3.3.2) applicable to one
or more administered items (3.3.1)
Note 1 to entry: The responsibility for the registration of metadata may be different from the responsibility for
stewardship of metadata.
3.4.2
stewardship organization
StO
organization (3.3.9) that maintains stewardship (3.4.1) of an administered item (3.3.1)
Note 1 to entry: In the second edition of ISO/IEC 11179-6, this was called responsible organization.
3.4.3
submission organization
submitting organization
SuO
organization (3.3.9) that submits a metadata item (3.2.17) for registration (3.3.23)
8 © ISO/IEC 2015 – All rights reserved

3.5 Specific terms used in this part of ISO/IEC 11179
3.5.1
data construct
object (3.2.22) a metadata item (3.2.17) describes
Note 1 to entry: Individual data elements, value domains, data element concepts, conceptual domains, object
classes, and properties are data constructs.
3.5.2
quantity
permissible value (3.3.20) associated with a unit of measure (3.3.29)
4 Theory of terminology
This clause describes the concepts from the theory of terminology that are used in this part of
ISO/IEC 11179. They are mostly taken from ISO 704 and ISO 1087-1. They provide the background and a
more thorough explanation of the theory of terminology.
In the theory of terminology, an object is something conceivable or perceivable. Concepts are mental
constructs, units of thought, or units of knowledge created by a unique combination of characteristics.
Concepts are organized or grouped by characteristics, which are also concepts. Any concept may be a
characteristic; being a characteristic is a role for a concept. Essential characteristics are indispensable
to understanding a concept, and they differentiate them, though which characteristics are essential
depends on context. For instance, the concept person has sex, age, marital status, educational
attainment, and race/ethnicity as essential characteristics in demography; however, it has name, sex,
date/time of birth, height, weight, and mother’s name as essential characteristics in a birth records
system. For zoology, the essential characteristics of a person are different still. Other characteristics
are inessential. The sum of characteristics for a concept is called its intension. The totality of objects a
concept corresponds to is its extension.
In natural language, concepts are expressed through definitions, which specify a unique intension
and extension.
A designation (term, appellation, or symbol) is the representation of a concept by a sign, which denotes it.
A general concept has two or more objects that correspond to it. An individual concept has one
object that corresponds to it. That is, a general concept has two or more objects in its extension, and an
individual concept has one object in its extension.
A concept system is set of concepts structured according to the relations among them. A terminological
system is a concept system with designations for each concept.
5 Metadata
5.1 General
For ISO/IEC 11179 (all parts), metadata is defined to be data that defines and describes other data.
NOTE In general, metadata is descriptive data about an object; in ISO/IEC 11179 that object is “data”.
This means that metadata are data, and data become metadata when they are used in this way. This
happens under particular circumstances, for particular purposes, and with certain perspectives, as no
data are always metadata. The set of circumstances, purposes, or perspectives for which some data are
used as metadata is called the context. So, metadata are data about data in some context.
Since metadata are data, then metadata can be stored in a database and organized through the use of a
model. Some models are very application specific, and others are more general. The model presented and
described in ISO/IEC 11179-3 is general. It is a representation of the human understanding of the metadata
© ISO/IEC 2015 – All rights reserved 9

needed to describe data constructs, including the relationships that exist among that metadata, and not
necessarily how the metadata will be represented in an application of an MDR. A model of this kind is
called a conceptual model. Conceptual models are meant for people to read and understand.
Models that describe metadata are often referred to as metamodels. The conceptual model presented
in ISO/IEC 11179-3 is a metamodel in this sense.
5.2 Concepts
5.2.1 General
Several data constructs used in ISO/IEC 11179 are concepts. They are data element concept, object class,
property, conceptual domain and value meaning. These are discussed in more detail in 5.3 and 5.5.
The semantics of data come from the concepts used in their descriptions. The meanings of all the
concepts used to describe a datum are combined into a story, sometimes called a fact. This is equivalent
to the information conveyed by some datum.
As ISO/IEC 11179-5 describes, the names for data elements, which may convey some of the semantics
of their underlying data, can be constructed from the designations of their constituent concepts. So,
for some datum, the story it conveys might be written as “The temperature in Washington, DC at the
bottom of the Washington Monument on 14 June 2013 at 1600 ET was 78 °F”. The designations of
concepts (temperature; Washington, DC; Washington Monument, 1600 ET, and 78 °F) are interspersed
with English words to create a sentence, which contains the story.
Finally, the relationships some concepts have with others, as defined in a concept system, add semantics
to data. For instance, the concept of a temperature measurement is different if it is a measure of the
kinetic activity of molecules of air in some location on Earth versus a measure of ambient infrared
radiation in inter-planetary space between Jupiter and Saturn. In both cases, instances of temperature
are ultimately measures of infrared radiation, but they are obtained far differently. The temperature of
air is directly determined by the motion of molecules. There are far too few molecules in inter-planetary
space for the same kind of measurement to be meaningful. A different sort of measurement is required.
5.2.2 Management
Looking across all the data elements found in an organization or across organizations, one finds many
concepts that are the same. For instance, in statistical survey organizations, data are collected and
estimates produced for some population. But surveys are often conducted on a regular basis – monthly,
quarterly, yearly – so the population is repeated. Moreover, many surveys might be conducted on the
same population, each for its own specialized purpose. A similar situation applies in a scientific research
laboratory, where in a large program, the same scientific experiments are conducted repeatedly.
Since some of the purposes of the MDR are understanding, re-use, harmonization, and standardization
of data, then managing meanings is critical for those needs. In the case of re-use in particular, where
the same meanings are applied in different situations, it is inefficient, error prone, redundant, and
inhibitory to store one concept multiple times. If the same concept is used to describe many data
elements, describe it once and re-use it.
5.3 Fundamental model of data elements
For the purposes of ISO/IEC 11179 (all parts), a data element comprises two parts:
— Data element concept,
— Value domain.
A data element concept also comprises two parts:
— Object class,
10 © ISO/IEC 2015 – All rights reserved

— Property.
Figure 1 illustrates the fundamental model of data elements.
Data Element
Data Element Concept
Object Class
Property
Value Domain
NOTE In Figure 1, if a Region B is contained within the boundary of a Region A, then the Region A comprises
the Region B (and possibly others).
Figure 1 — Fundamental, informal model of a data element
The totality of objects for which we wish to collect and store data is the extension of an object class.
Object classes are concepts, and they correspond to the notions embodied in classes in object-oriented
models and entities in entity-relationship models. Examples are cars, persons, households, employees,
jobs, and orders. Properties are what humans use to distinguish or describe object classes. They are
characteristics, not necessarily essential ones, of the object class and form its intension. They are also
concepts, and they correspond to the notions embodied in attributes (without associated datatypes)
in object-oriented or entity-relationship models. Examples of properties are colour, model, sex, age,
income, address, salary or price.
An object class may be a general concept. This happens when the totality of objects corresponding to
the object class has two or more members. The examples in the previous paragraph are of this type.
Record level data are described this way. On the other hand, an object class may be an individual
conc
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