There would be no point in selecting and organizing resources if they could not be accessed or interacted with in some way. Organizing systems vary a great deal in the types of resource-based interactions they enable and in the nature and extent of access they allow.
It is essential to distinguish the interactions that are designed into and directly supported by an organizing system from those that can take place with resources after they have been accessed. For example, when a book is checked out of a library it might be read, translated, summarized, criticized, or otherwise used—but none of these interactions are directly designed into the library. We need to focus on the interactions that are enabled because of the intentional acts of description or arrangement that transform a collection of resources into an organizing system. Note that some of these “designed interactions” might be explicitly supported in an organizing system containing digital books, as in Google’s search engine where language translation is a supported service.
Users have direct access to original resources in a collection when they browse through library stacks or wander in museum galleries. Users have mediated or indirect access when they use catalogs or search engines, and sometimes they can only interact with copies or descriptions of the resources.
The concept of affordance, introduced by J. J. Gibson and then extended and popularized ...