ELI5: affordances and signifiers

What are affordances and signifiers?

Affordances are the natural ways you can use something—like how a button naturally invites you to push it or a handle invites you to pull [1][2]. Signifiers are the visual clues that tell you what to do, like a picture of a hand pointing at something or a sign that says "Push" [3].

Why do we need both?

Sometimes an object can do something, but you won't know it unless someone tells you how [2]. Imagine a door that's perfectly fine but has no handles—you wouldn't know to push or pull it! That's why signifiers help make things clear [3].

What's the difference?

Affordance is what something CAN actually do, while a signifier is what TELLS you what it can do [2][3]. The door handle is a signifier that shows you where to grab, and the actual pulling motion is the affordance [1].

Real-world examples

A light switch naturally affords being flipped up and down, and the small switch itself is the signifier that shows you where to interact [1]. Video game designers use signifiers like glowing objects to show you which things you can pick up [7].