2 Normative references

The following standards contain provisions which, through reference in this text, constitute provisions of this part of ISO 10303. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this part of ISO 10303 are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. Members of IEC and ISO maintain registers of currently valid International Standards.

• ISO 10303-1, Industrial automation systems and integration - Product data representation and exchange - Part 1: Overview and fundamental principles.
• ISO 10303-11, Industrial automation systems and integration - Product data representation and exchange - Part 11: Description methods: The EXPRESS language reference manual.
• ISO 10303-21, Industrial automation systems and integration - Product data representation and exchange - Part 21: Clear text encoding of the exchange structure.
• ISO 10303-31, Industrial automation systems and integration - Product data representation and exchange - Part 31: Conformance testing methodology and framework: General concepts.
• ISO 10303-41, Industrial automation systems and integration - Product data representation and exchange - Part 41: Integrated generic resource: Fundamentals of product description and support.

3 Terms, definitions, and abbreviations

3.1 Terms defined in ISO 10303-1

This part of ISO 10303 makes use of the following terms defined in ISO 10303-1.

• application;
• application protocol;
• integrated resource;
• product;

3.2 Terms defined in this part of ISO 10303

3.2.1
class
set
type
sort
category
family
space
things of a common nature

NOTE - A class is an abstract concept that can be defined even if the number of things of that nature is zero.

NOTE - The terms 'class' and 'set' are sometimes distinguished, so that:

• things of a common nature specified by means of a criterion for inclusion is called a class; and
• things of a common nature specified by enumerating them is called a set.

This distinction is not used by this part of ISO 10303.

NOTE - A requirement specification is a class. An individual product that meets the requirement is a member of the class.

NOTE - A design specification or product type is a class. An individual product that complies with the design is a member of the class.

NOTE - A space is a class. A space can contain physical things, such as the space of points within the volume of a product, or the space of states within an activity. A space can contain abstract things, such as the space of real numbers.

Usually the term 'space' implies that there is a nearness metric defined over the members of the class.

NOTE - This definition of class is consistent with the definition of 'product class' in ISO 10303-41, 'maths space' in ISO 10303-50, and 'class' in ISO 15926.

3.3 Abbreviations