ISO 2108:2017 establishes the specifications for the International Standard Book Number (ISBN) as a unique international identification system for each product form or edition of a separately available monographic publication published or produced by a specific publisher that is available to the public. It specifies the construction of an ISBN, the rules for its assignment and use, the metadata to be associated with the ISBN allocation, and the administration of the ISBN system. ISO 2108:2017 is applicable to monographic publications (books), not to textual works (content). Monographic publications include individual sections or chapters where these are made separately available and certain types of related products that are available to the public irrespective of whether those publications are made available for sale or on a gratis basis. Examples of applicable and non-applicable products are provided in Annex A. NOTE – More detailed, operational guidance is provided in the latest version of the Users' Manual available from the Registration Authority for this document (see Clause 7).