US Patent 7272786 Metadata, models, visualization and control

A method or data processing system readable medium can be used for modifying a target document. The data processing system medium or method may use metadata and rendering instructions to modify a target document to make the target document more user-friendly, more informative, or easier to track statistics related to the target document. In modifying the document, the rendering instructions render the metadata elements that can be used in the target document. In some embodiments, different sets of metadata and rendering instructions may be used with the same target document.