Preface Standards development within the Information Technology sector is harmonized with international standards development. Through the CSA Technical Committee on Information Technology (TCIT), Canadians serve as the Canadian Advisory Committee (CAC) on ISO/IEC Joint Technical Committee 1 on Information Technology (ISO/IEC JTC1) for the Standards Council of Canada (SCC), the ISO member body for Canada and sponsor of the Canadian National Committee of the IEC. Also, as a member of the International Telecommunication Union (ITU), Canada participates in the International Telegraph and Telephone Consultative Committee (ITU-T). Scope This part of ISO/IEC 13250 specifies a data model of Topic Maps. It defines the abstract structure of Topic Maps, using the information set formalism, and to some extent their interpretation, using prose. The rules for merging in Topic Maps are also defined, as are some fundamental subject identifiers. The purpose of the data model is to define the interpretation of the Topic Maps interchange syn-taxes, and to serve as a foundation for the definition of supporting standards for canonicalization, querying, constraints, and so on. All of these standards fall outside the scope of this part of ISO/IEC 13250. NOTE 1 This clause defines the scope of this part of ISO/IEC 13250. It should not be confused with the concept of \"scope\" defined in 5.3.3, which only applies in the context of Topic Maps. NOTE 2 This part of ISO/IEC 13250 does not have a conformance section since it is only a data model, and as such it has no boundary with the outside world in terms of which conformance can be specified.