The system of cultural, historical, or other textual knowledge that a reader brings to a text and that makes it possible to understand it. Such knowledge is sometimes thought of as the possession of a script or stereotype. For example, the reader of a novel knows the sort of thing that goes on when one visits a restaurant; hence on being told that the party was seated, she can fill in that they were seated facing a table rather than facing a wall, all at the same table, on chairs rather than on each other, and so on. The frame problem in artificial intelligence research emphasizes the pervasive need for such knowledge.