a user interface for improving document layout on arbitrary devices of different resolutions and size using manifold representations of content . manifold representations of content are : multiple versions of anything that might appear in a document , from text , to images , to even such things as stylistic conventions . the specific content is selected and formatted dynamically , on the fly , by a layout engine in order to best adapt to a given viewing situation . a user interface for authoring and editing such manifold content is disclosed .