• When facing a device, we seeking for clue about how to use. Designer need provide it.
    Otherwise, we need use our own creativity and imagination.
  • Misleading signifier: a row of vertical pipes across a service road in a public park
    • Pipes blocks cars
    • Park vehicle go through the pipes
  • Affordances: possible interactions between people and environment.
  • Perceived affordance often acts as signifier, but they can be ambiguous
  • Signifiers signal things, indicate what actions are possible and how to be done. Signifier must be visible.