Affordances: Clarifying and Evolving a Concept

The concept of affordance is popular in the HCI community but not well understood. Donald Norman appropriated the concept of affordances from James J. Gibson for the design of common objects and both implicitly and explicitly adjusted the meaning given by Gibson. There was, however, ambiguity in Norman’s original definition and use of affordances which he has subsequently made efforts to clarify. His definition germinated quickly and through a review of the HCI literature we show that this ambiguity has lead to widely varying uses of the concept. Norman has recently acknowledged the ambiguity, however, important clarifications remain. Using affordances as a basis, we elucidate the role of the designer and the distinction between usefulness and usability. We expand Gibson’s definition into a framework for design.