Exhibit visitors will always make their own meanings in the spaces we create; all we can do is offer them chances to make meanings related to our mission. I like thinking about these opportunities as affordances, a term borrowed from industrial design.
Don Norman used the term in his 1988 Psychology of Everyday Things. User interface designers and education researchers picked up the word, and exhibit planners have sometimes used it, too.
Norman used the example of door operation to explain affordances. When you approach a door, can you tell if it opens toward or away from you? When you grasp the doorknob, do you know whether to push or pull? Norman pointed out that some designs made the door's operation clear, while others obscured it. In this photo [>], the bar mechanism better affords pushing than pulling to open the door.
In exhibit planning, we create affordances for visitors so that they are more likely to think about the concepts or have the kind of experiences that we're aiming for. An affordance might be accessible language, lower positioning of objects meant to engage children, or a particular lighting effect. When the writer, the exhibit designer, and the lighting designer all understand the exhibit's goals, they're in a better position to create affordances that help an exhibit succeed in accomplishing those goals.