In a cell based EUI, existing display container cells nested within a "host" display container cell are automatically shifted and/or downsized, if necessary, to increase available space to facilitate the creation of another display container cell nested within the "host" display container cell, in response to a request to perform the creation. Similar shifting and/or downsizing are performed to facilitate expansion of one of the nested display container cells; and shifting and upsizing are performed to facilitate contraction of one of the nested display container cells. Like kind of shifting and/or downsizing/upsizing are performed on existing display container cell to facilitate creation, expansion or contraction of a display action cell. The hierarchical relationship of the display container and action cells, and the automatic relative resizing of the container and action cells enable user interactions otherwise unavailable under prior art EUI.