Indexed Sequential Access
Up to this point, we have had to choose between viewing a file from an indexed point of view or from a sequential point of view.
Here, we are looking for a single organizational method that provides both of these views simultaneously.
Why care about obtaining both views simultaneously? If an application requires both interactive random access and cosequential batch processing, both sets of actions have to be carried out efficiently. (E.g., a student record system at a University).