The Design of Everyday Things

By Don Norman
Second Edition

• If you struggle to use a tool, consider that the tool is poorly designed
• Signs are a failure of design
  • If you have to tell the user how a door works, you've failed.
• Affordance vs signifier
  • An Affordance is something an app (or tool) can do
    • You can shuffle a card, turn it, lift it, discard it, or flip it. These are affordances
    • You can turn a knob, or pull it.
  • A signifier is a sign that reflects an affordance
    • A card indicates (maybe with a shadow) that it can be swiped or elevated or flipped.
  • Some people use affordance to mean signifier "can we add an affordance to make it clear that the user can do XYZ" aaagh!
  • Affordances are great for the physical world because a lever implies sliding, a knob turning, and so on. On UI it's harder to evoke those affordances, so we need to rely on signifiers.

See Also

#categorization
#models