A false affordance is an apparent affordance that does not have any real function, meaning that the actor perceives nonexistent possibilities for action.[11] A good example of a false affordance is a placebo button.[12] A hidden affordance indicates that there are possibilities for action, but these are not perceived by the actor. For example, it is not apparent from looking at a shoe that it could be used to open a wine bottle. For an affordance to be perceptible, there is information available such that the actor perceives and can then act upon the existing affordance.