https://medium.com/@DEJIDOPE/summary-of-design-of-everyday-things-by-don-norman-f06f023fdc95
It is the relationship between the elements of two sets of things. The relationship between a control and it’s results are easiest to understand when there is an understandable mapping between the control and it’s results. Controls should be close to the items been controlled. For example, light switches in hall are usually arranged in such a way that a user will immediately know which switch controls which light.
Signifiers help users know what affordances a product has and how to use them. They are used when a product’s affordances are not easily perceived. Signifiers are signals. Some signifiers are signs, labels that tell the users what to do.
Conceptual models/Mental models are the understanding in the minds of users of how certain products work. In our daily life, we create a conceptual or mental model about everything we interact with. We use that knowledge while interacting with new things.
Affordances are the possible actions a person can perform with a particular object/product. For example, a chair affords sitting. If an affordance cannot be easily perceived by a user, a means of signaling it’s presence is required. Affordances determine what actions are possible.
