It’s Not You, It’s the Interface

Ben Olson
4 min readFeb 3, 2017


More specifically, it’s the Affordance/Signifier relationship

In my struggle to resolve a user interface design problem, I recently returned to the bible of user experience for a little clarity: The Design of Everyday Things by Don Norman.

I discovered that I was guilty of confusing affordance and signifier as Norman predicted. But when I put the terms in the context of designing a mobile interface, the distinction became clear and meaningful.

What is an affordance?

An affordance is what an object can do. Yet what an object can do is only revealed by a user. Therefore an affordance is what an object can do based on a user interaction. An affordance can be obvious or hidden.


A chair reveals its affordance by design, its shape mirrors the body and communicates its intent: to be sat on.

However, a chair has an additional affordance not communicated by its design. A chair can be used to change a lightbulb or reach a book, a hidden affordance.

Clearly an object’s affordance is not determined solely by design but by the way a user interacts with it. An object’s affordance is determined by user interaction.

What is a signifier?

A signifier clarifies an affordance, it illustrates or describes what an object can do. A signifier can be blatantly obvious or very subtle.


Some chairs have seats that are concave, shaped like a pair of butt cheeks. This design detail is subtle but acts as a signifier of the object’s purpose. Regardless of that signifier, the chair’s affordance is the same, it can be sat on or stood on — the signifier encourages its preferred use.

A door may have a slot. The slot is an affordance — objects may be placed through the hole. However the slot may be accompanied by the text “Mail” which is a signifier that indicates the purpose of the affordance by offering instructions on what objects should be placed through the hole.

Signifiers can be as obvious as a hand written sign taped to a door or as subtle as a texture or an audio cue.



Ben Olson

Ben Olson is a Brooklyn based designer committed to delivering meaningful, user-centered experiences that educate and inspire.