…because some thoughts are worth remembering
Don Norman, the author of The Design of Everyday Things, is known for appropriating the term, affordance, to human-machine interaction, recognized the need for affordances in the virtual world, signifiers.
Affordance describes the relationship between an object and an organism that affords the opportunity to perform an action. For example, a handle bar that’s placed vertically on a door signals to you that the door should be pulled (rather than pushed). But if there is just a flat bar placed horizontally across a door signals to you that the door should be pushed. A knob on the door, however, signals you to twist or turn. This language is so powerful that a toddler picks up on these cues, as evidenced by a child’s eagerness to push, not pull or twist, all the elevator buttons.
In the second edition of The Design of Everyday Things, Norman introduces another word, signifier, to discuss the visual cues you get to interact with virtual items. Although I’ve heard the term virtual affordances, it makes sense to have a separate word, since the flat surface of an iPad or a touch screen affords people to touch over the entire surface, but certain graphic element (such as a rectangular border shaded in grey) within the display signifies where one should touch for specific actions to occur.
Thanks to my brother-in-law for the updated information from the second edition. I wish everyone in usability design and app developers read and learned from Norman’s work.
Here’s a great blog post by Norman on designers communicating to users through affordances.
Photo: Florence, Italy