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 SCC Mirror Committee (SMC) 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). For brevity, this Standard will be referred to as "CAN/CSA-ISO/IEC 26550" throughout. At the time of publication, ISO/IEC 26550:2015 is available from ISO and IEC in English only. CSA Group will publish the French version when it becomes available from ISO and IEC. Scope This International Standard is the entry point of the whole suite of International Standards for software and systems product line engineering and management. The scope of this International Standard is to provide the terms and definitions specific to software and systems product line engineering and management, define a reference model for the overall structure and processes of software and systems product line engineering and management and describe how the components of the product line reference model fit together, and define interrelationships between the components of the product line reference model. This International Standard does not describe any methods and tools associated with software and systems product line engineering and management. Descriptions of such methods and tools will appear in the consecutive International Standards (ISO/IEC 265511) to ISO/IEC 265562)). This International Standard does not deal with terms and definitions addressed by ISO/IEC/IEEE 24765:2010 that provides a common vocabulary applicable to all systems and software engineering work. Whenever this International Standard refers to "products", it means "system-level products" consisting of software systems or both hardware and software systems. It may be useful for the engineering and management of product lines that consist of only hardware systems but it has not been explicitly created to support such hardware product lines. This International Standard is not intended to help the engineering, production, warehousing, logistics, and management of physical items that, possibly combined with software, comprise the products. These processes belong to other disciplines (e.g. mechanics, electronics). NOTE Annex A provides further information on products. This International Standard, including the product line reference model and the terms and definitions, has been produced starting from References [6], [7], and [8] which finally resulted in a broad consensus from National Member Bodies at the time of publication. In addition to this background process, structures from ISO/IEC 12207:2008, ISO/IEC/IEEE 15288:2015, ISO/IEC 15940:2006 and ISO/IEC 14102:2008 have been used as a baseline.