An EUI for presenting contents to a user, is constituted with at least a first display container cell, a second display container cell nested within the first display container cell, and a display action cell nested in either the first or the second display container cell. In one embodiment, each display container/action cell is defined by a plurality of cell attributes. The container cell attributes of each container cell include attributes defining a kernel, a maximum state, a centroid, a relocatability, and a resizing priority. The container cell attributes may also include attributes defining the maximum number, placement and alignment of descendant container/action cells. The container cell attributes of a leaf container cell also include an attribute defining content type of content to be rendered in the leaf container cell. The action cell attributes include attributes defining an image and/or binaries to be executed for various user actions.