Affordance

The notion of affordance is a critical component of Gibson's (1979) ecological theory of perception. According to Gibson (p. 127) "the affordances of the environment are what it offers the animal, what it provides or furnishes, either for good or ill." More specifically, an affordance is information from the environment that offers a potential action from an agent. Thus, affordances cannot be deemed to be solely in the domain of the world, nor solely in the domain of the agent, but depend upon the relationship between an embodied agent and its world. Differences in bodily structures between agents dictate differences in affordances. Affordances "have to be measured relative to the animal. They are unique for that animal. They are not just abstract physical properties" (p. 127).

Affordances, and ecological perception, are of increasing interest in recent work on embodied cognitive science (Robbins & Aydede, 2009). They are also important in modern theories of design (Norman, 2002).

References:

1. Gibson, J. J. (1979). The Ecological Approach To Visual Perception. Boston, MA: Houghton Mifflin
2. Norman, D. A. (2002). The Design Of Everyday Things (1st Basic paperback. ed.). New York: Basic Books
3. Robbins, P., & Aydede, M. (2009). The Cambridge Handbook of Situated Cognition. Cambridge ; New York: Cambridge University Press.

(Added October 2009)