What are Signifiers?
Signifiers are perceptible cues that designers include in (e.g.) interfaces so users can easily discover what to do. Signifiers optimize affordances, the possible actions an object allows, by indicating where and how to take action. Designers use marks, sounds and other signals to help people perform appropriate tasks.
“Good design requires, among other things, good communication of the purpose, structure, and operation of the device to the people who use it. That is the role of the signifier.”
— Don Norman, “Grand Old Man of User Experience”
See why signifiers are vital to good design.
Signifiers are Old and New
If you have ever studied semiotics (i.e., the study of signs and symbols), linguistics or film, you may have come across signifiers before. Generally speaking, a signifier is something that points to or indicates something else. In the 2013 edition of his book The Design of Everyday Things, Don Norman introduced the term to the field of design, and used it to refer to perceivable cues about the affordances — the actions that are possible for a person to take — with a designed object.
Signifiers Should Guide People
Affordances define and determine what we can do with objects. For example, a door affords opening; a touchscreen affords touching (something on-screen); a ceiling-to-floor picture window affords viewing (hopefully, picturesque scenery). However, affordances can be problematic when:
A perceived affordance is misleading. E.g., a door is pullable, but its flat horizontal handle hints that people should push it open.
People have no clue what to do. E.g., a poorly designed touchscreen fails to indicate where to touch and how (e.g., tap or slide) to achieve a goal.
People can’t detect an anti-affordance (something that works against the affordance). E.g., someone accidentally walks into that picture window and gets badly bruised.
That’s why we as designers must direct people who encounter our products to affordances whenever these aren’t clear as well-designed perceived affordances. So, we include signifiers to specify how people discover the possibilities of affordances and communicate where the action should take place. Namely, we design easily findable labels, arrows, icons, sounds and other signals to lead people to take the right actions to use our digital and physical products.
Learn the difference between affordances, perceived affordances and signifiers using the example of an airplane meal.
The people who use our designs are easily frustrated. They have things to do (e.g., bills to pay), sometimes in stressful circumstances, and even the smallest detail (or lack of it) can make or break a seamless experience. Users shouldn’t have to pause to figure out what to do. And if you accidentally design a perceived affordance that sends the wrong signal, you can delay them (or worse). For example, while on sabbatical at Cambridge University, England, in the 1980s, cognitive science and usability engineering expert Don Norman found he had trouble even using some doors thanks to confusing handles. Norman later introduced the term “signifier” because so many people in the design community were misusing the concept of affordances. Affordances are possible interactions; signifiers are design properties that announce affordances. We need both.
Learn more about “Norman doors” and the difference between good and bad design.
Norman further describes how affordances and signifiers can exist dependently and independently. Depending on the context, affordances without signifiers and signifiers that mislead can be dangerous: another reason we must craft controls that prove we fully empathize with the people we design for and understand their needs. Don Norman was among the experts consulted following 1979’s Three Mile Island nuclear power plant accident. There, the control room’s design was flawed enough to help fail to prevent a disaster. Although it's an extreme case, a glance at the cost of confusion is enough to highlight the value of signifiers: discoverability and understanding are crucial in human-centered design.
The IxDF landing page features signifiers: e.g., the microcopy “Advance my career now >” clearly signals that blue button’s purpose.
How to Use Signifiers Best
Along with having a good grasp of design principles, ensure that you:
Clearly indicate where and how people should interact with your website, app or physical product, including the gestures they need to use. For example, should they tap, slide sideways or scroll upwards on your app? If it’s voice-controlled, use a combination of visual (e.g., lights) and auditory signifiers (e.g., vocal cues) to guide them.
Match each perceived affordance to the actual affordance and beware of false affordances. For example, an envelope icon should function as an “email us” button, not reveal a physical address.
Use signifiers consistently. Familiarity is key; don’t make people pause to think. For example:
A large green button to indicate pressing to “Submit”.
Greyed-out text fields to prevent people from entering unnecessary information.
Communicate the purpose with clues as to what to do, what is happening and what alternative actions people can perform. As people will develop their mental model of your product (i.e., the look, feel and operation of it) based on the system image (i.e., what they make of the physical structure they encounter), always design to empathize with them. People make mappings from design parts that appear to be controls, etc., to resulting actions, and the constraints in your design will limit what they can do and help keep them on track.
Remember all the senses, not just seeing and hearing, but also tactile (touch), vestibular (movement) and proprioceptive (body awareness). So, consider where (e.g.) vibrations might act as appropriate signifiers. Furthermore, by designing for accessibility, you can help optimize everyone’s experience.
Overall, you converse with people through your design. When you leverage their knowledge of how the world works and anticipate their needs, you can minimize the risk of uncertainty in good experiences.
Learn More about Signifiers
Read Don Norman’s groundbreaking The Design of Everyday Things for in-depth insights about signifiers and other design topics: https://jnd.org/the-design-of-everyday-things-revised-and-expanded-edition/
Take our course covering aspects of signifiers, affordances and more: https://www.interaction-design.org/courses/affordances-designing-intuitive-user-interfaces
Don Norman offers many thought-provoking insights here: https://jnd.org/signifiers_not_affordances/
Literature on Signifiers
Here’s the entire UX literature on Signifiers by the Interaction Design Foundation, collated in one place:
Learn more about Signifiers
Take a deep dive into Signifiers with our course Affordances: Designing Intuitive User Interfaces .
Affordances are a key concept for designers. If you want to build products that are intuitive and easy to use, fully understanding the relationship between the human mind and technology is crucial. An “affordance” refers to the possibility of an action on an object; for instance, we say that an elevator button affords being pressed, and a chair affords being sat on. The concept was popularized by HCI (human-computer interaction) expert Don Norman in the late 1980s, and it has since played an essential role for user experience professionals and researchers. Understanding this term is essential for anyone who wants to get a deeper appreciation of what it means for a product to be “intuitive.”
Taking this course will teach you both the theory of affordances and also how to build instantly perceptible affordances into your own designs. Your users should be able to identify the actions afforded by a design with speed and accuracy. Thus, the better you can make your affordances, the more likely you will prevent the user from becoming frustrated (which can happen very quickly). In order to achieve this, you as a designer must appreciate how users perceive the world and how experience, context, culture, constraints and other factors affect our ability to detect the possibilities of actions on offer. This is at the heart of why those interested in a design career and established designers alike must gain a firm grounding in the meaning and potential application of affordances as a designer’s tool.
Throughout the course, we identify the major milestones in the evolution of the term “affordance” and outline how it applies to practical user experience (UX) design. Along the way, we look at the affordances of objects in the real world and screen-based interfaces so as to reinforce the concepts and principles covered in each lesson. You will soon realize how vital a solid grasp of affordances is—the name of the game is to make designs that users can take to naturally and without having to hesitate to ask themselves, “What happens if I do this?”.