Models and Theories in Human-Computer Interaction/Norman's Affordances and Mapping

In Norman’s The Psychology of Everyday Things, he mentioned that affordance provide strong clues to the operations of things. When possible actions and consequences are easily figured out by first time users, it is very likely that this device or system is easy to use. Visibility is closely connected with affordance, so does mapping. To correctly understand the design or perform the operations, user need to rely on their mapping ability.

To my own experience, most of the time when there’re problems in design, mapping is one of the main causes. Mobile devices have bigger issues in the mapping and affordance, especially on small screen ones. Automobile dash board doesn’t have much trouble in this case as there are plenty room to display the controls. The mapping could be natural and clear.

On mobile device, there are not enough space to display all functions in most cases, so less important ones need to be hide under certain subcategories. Thus the visibility of affordance is not clear. On other cases, there are not enough space to display text labels. The labels serve as reminders if user forgets the functions. Latest app design tend to use just icons to represent meanings instead of icons plus text labels. Like the navigation bar of Instagram. This could be a big problem for older groups as the mapping is not clear to them. But I guess seniors are not the target group of Instagram, so they tend to do it their way to attract young people. Another mapping relates to users’ previous experience. Users may have been educated to behave in some way, so to make the mapping work, designers should follow that behavior. Through the usability study of an app I designed last semester, I found out that half of the users failed on the delete function. It is because they tend to drag the item to the trash can whereas my initial design failed to do so.