Week 4 / Third Lecture: Understanding and conceptualizing interaction [Weiting]

..Affordance..

"...the term affordance refers to the perceived and actual properties of the thing, primarily those fundamental properties that determine just how the thing could possibly be used. [...] Affordances provide strong clues to the operations of things. Plates are for pushing. Knobs are for turning. Slots are for inserting things into. Balls are for throwing or bouncing. When affordances are taken advantage of, the user knows what to do just by looking: no picture, label, or instruction needed." (Norman 1988, p.9)

[ Source : http://www.interaction-design.org/encyclopedia/affordances.html ] 

 An affordance is a quality of an object, or an environment, which allows an individual to perform an action. For example, a knob affords twisting, and perhaps pushing, while a cord affords pulling. The term is used in a variety of fields: perceptual psychology, cognitive psychology,environmental psychology, industrial design, human–computer interaction (HCI), interaction design, instructional design and artificial intelligence. (From : Wikipedia)

The word "affordance" was originally invented by the perceptual psychologist J. J. Gibson (1977, 1979) to refer to the actionable properties between the world and an actor (a person or animal). To Gibson, affordances are a relationship. They are a part of nature: they do not have to be visible, known, or desirable. Some affordances are yet to be discovered. Some are dangerous. I suspect that none of us know all the affordances of even everyday objects.  

[Source : http://www.jnd.org/dn.mss/affordances_and_design.html ]

Affordance in GUI's (Graphical User Interfaces)

A graphical user interface or GUI (pronounced GOO-EE) can be defined as a connection between users and the underlying system through physical aspects of the system such as buttons, icons, scroll bars, pop-up or pull-down menus, messages, colours, and pictures (Preece, 1993; Newman and Lamming, 1995). GUIs save us a lot of time and effort in performing actions that would otherwise be a hassle to execute.

[Source : http://ahsmail.uwaterloo.ca/kin356/afford/gui.htm]

• Important Concept
• Buttons drawn as 3D shapes appear to "stick out" and afford pushing.

Summary : 

• All design is persuasive.
• Profitable to the client = profitable to the user.
• The customer is the King. Customer is always right.

Further study recommend :

1. The Concept of Affordance in Usability. 

[ http://research.cs.vt.edu/usability/projects/uaf%20and%20tools/affordance.htm ]

2. The Use and Evaluation of Affordance in HCI 

[ http://www.irma-international.org/viewtitle/13191/ ]