1. A data structure associated with an hierarchical file system of a computational system, the hierarchical file system comprising a set of files arranged in a directory structure comprising a set of directories, the files having as type word processing document, spreadsheet document, presentation document or a diagramming document, or multi-media file, the data structure comprising: a data store, the data store comprising a set of reference data objects (topics) and a set of coupling data elements, wherein the set of coupling data elements comprise at least: one coupling data element for coupling a first item selected from either the set of reference data objects or the set of files or the set of directories with a second other item from either the set of reference data objects or the set of files or the set of directories.