At times, the intersection of universal design and inclusive design is difficult to determine through the literature. Some authors (e.g. Abascal, 2005) use the terms interchangeably or with similar definitions. However Keates, Harrison, Clarkson, Robinson, 2000 hints at a difference between the concepts. Universal design is a much more discussed topic in the literature, perhaps because of its relevance to other fields, such as product design and architecture. Universal design attempts to design a product that is usable by as many users as possible. When used as a different concept, inclusive design seems to advocate an educated selection of specific user populations to design for. In addition, the terms of universal usability and design for all are also used in some articles. Furthermore many authors attempt to build off these well-known concepts to create their own terms, such as “user sensitive inclusive design” (Newell & Gregor, 2000) and the “user inclusive cube” (Keates, Harrison, Clarkson, Robinson, 2000).