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Affordance
When an element shows its purpose
Description
The affordance of an (UI) element should show the users what the user can do with that element without making the user think about it.
A well designed user interface has UI elements that show the users without further labelling or something similar what they were designed for.
Usability
A product, software and service all have a usability. The usability represents how easy it is to fulfil a goal with the solution t...