Seriously, this is actually very good... From wikipedia: http://en.wikipedia.org/wiki/Affordances
An affordance is the quality of an object, or an environment, that allows an individual to perform action. The term is used in a variety of fields: perceptual psychology, cognitive psychology, environmental psychology, industrial design, human–computer interaction (HCI), interaction design and artificial intelligence. As explained below, two different definitions have developed. The original definition describes all action possibilities that are physically possible; a refinement to that definition describes action possibilities that the actor is aware of. Affordances as action possibilities Psychologist James J. Gibson originally introduced the term in his 1977 article The Theory of Affordances[1] and explored it more fully in his book The Ecological Approach to Visual Perception[2] in 1979. He defined affordances as all "action possibilities" latent in the environment, objectively measurable and independent of the individual's ability to recognize them, but always in relation to the actor and therefore dependent on their capabilities. For instance, a set of steps which rises four feet high does not afford the act of climbing if the actor is a crawling infant. Gibson's is the prevalent definition in cognitive psychology. Jakob von Uexküll had already discussed the concept in the early twentieth century[3], calling it the "functional colouring" (funktionale Tönung) of objects. Affordances as perceived action possibilities In 1988, Donald Norman appropriated the term affordances in the context of Human–Machine Interaction to refer to just those action possibilities which are readily perceivable by an actor. Through his book The Design of Everyday Things,[4] this interpretation was popularized within the fields of HCI and interaction design. It makes the concept dependent not only on the physical capabilities of the actor, but also their goals, plans, values, beliefs and past experience. If an actor steps into a room with an armchair and a softball, Gibson's original definition of affordances allows that the actor may toss the recliner and sit on the softball, because that is objectively possible. Norman's definition of (perceived) affordances captures the likelihood that the actor will sit on the recliner and toss the softball. Effectively, Norman's affordances "suggest" how an object may be interacted with. For example, the size and shape of a softball obviously fits nicely in the average human hand, and its density and texture make it perfect for throwing. The user may also bring past experience with similar objects (baseballs, perhaps) to bear when evaluating a new affordance. Norman's 1988 definition makes the concept of affordance relational, rather than subjective or objective. This he deemed an "ecological approach," which is related to systems-theoretic approaches in the natural and social sciences. The focus on perceived affordances is much more pertinent to practical design problems from a human-factors approach, which may explain its widespread adoption. Norman later explained that this adaptation of the term had been unintended.[5][6] However, the definition from his book has become established enough in HCI that both uses have to be accepted as convention in this field. On Mar 20, 2008, at 8:04 AM, Jared Christensen wrote: > Chris, > > I don't think the second 'definition' you laid out is correct. > Affordance is not an object (metal plate), or a quality assigned to > an object (glossiness); it is the perceived action associated with or > communicated by an object. > > I can see where the issue might get confused, and perhaps some > designers just find it easier to explain affordance to clients by > pointing to the glossy shine of a button and saying "This is > affordance. Right here." > > Jared > ________________________________________________________________ Welcome to the Interaction Design Association (IxDA)! To post to this list ....... [EMAIL PROTECTED] Unsubscribe ................ http://www.ixda.org/unsubscribe List Guidelines ............ http://www.ixda.org/guidelines List Help .................. http://www.ixda.org/help
