28. A computer system including at least one processor for rendering page images on a display, comprising: an external component encapsulating code for modifying a behavior of one or more elements, the external component operable to be instantiated multiple times and operable to modify elements in a plurality of different HTML documents while being external to the HTML documents and wherein information associating the one or more elements with the external component is maintained in a cascading style sheet, wherein code for determining a behavior of the one or more elements is included in one or more extensible markup language (XML) namespaces that are defined externally to the HTML documents and that are associated with the external component; and at least one processing unit comprising a renderer connected to the display for rendering the page images, the renderer being configured to: modify one or more of the page images by accessing one or more of the XML namespaces associated with the external component to initiate drawing of information on the one or more of the page images based at least in part on code included in the one or more XML namespaces; make a plurality of calls to the one or more XML namespaces to initiate the drawing of the information on the one or more of the page images; and draw the information on the one or more of the page image responsive to one or more of the plurality of calls to the one or more XML namespaces; the renderer being further configured to: instantiate the external component to reveal one or more of the XML namespaces associated with the external component the one or more of the XML namespaces being external to the HTML document and specifying one or more behaviors to be applied to the one or more elements; and access the one or more XML namespaces to retrieve a new behavior to be applied to the representation of the one or more elements rendered on the page image, the new behavior being configured to enhance a default behavior for the one or more elements.
41. The system of claim 28 wherein the HTML document includes another element and information associating the another element with the external component, and wherein the renderer is configured to access the one or more XML namespaces for determining a behavior of a representation of the another element.