This document:

a)    introduces the concept of the semantic unit (SU);

b)    provides requirements and guidance on how to define the target resource(s) in an SU by adopting the “target” syntax from the Web Annotation Model;

c)    provides requirements and guidance on the extensible metadata platform (XMP) serialization syntaxes for SU.

This document broadens the concept of XMP specified in ISO 16684-1 so that XMP can be used to describe an SU. A new flexible way of defining and describing SUs aims to bring innovation to textual and non-textual content, metadata, linked data, big data and artificial intelligence.