In Elastic Windows, a hierarchy of windows can be collapsed into a hierarchicon providing an overview of those windows (Figure ). A hierarchicon is an active thumbnail image of hierarchies of windows, which allows selection of any subhierarchy to be displayed on the screen.
A hierarchicon can be created for a hierarchy of windows by selecting the operation from the window menu. As a result, its hierarchicon is created with the large-scale image of the windows, and added to the overview window.
Clicking on different locations on the hierarchicon selects a subhierarchy (Figure ). Clicking with the left mouse button allows the user to select the subhierarchy one level down at the location of click. Clicking with the right mouse button selects the subhierarchy one level higher. The selected subhierarchy can be displayed on the original window location by clicking with the middle-mouse button click and selecting the peek menu option. Selected subhierarchy can also be dragged out of an hierarchicon and dropped anywhere on the existing window hierarchy, opening the selected subhierarchy as a result. The image of the hierarchicon is updated to reflect this operation after the selection is dropped.
Hierarchicons facilitate rapid access to a hierarchy of windows. However, they best serve their purposes when the content of windows is rich with images or the text is well-structured. Although, location of windows can also be used as a cue in the selection it probably demands more cognitive effort.