Abstract: An interactive, tree structured, graphical visualization aid enables a user to better understand and interpret underlying structures in collections of digitally stored data elements, such as documents, programs and other data files. The visualization aid responds to user input, which directs the aid to operate in one of at least two modes. In a first mode, the visualization aid displays a graphical tree structure that includes a selected node and all branches of the selected node, including all subordinate nodes and data elements. In this first mode of operation, all data elements or documents branching either directly from the selected node or directly from subordinate nodes are displayed in the tree structure as branching directly from their respective nodes.