1. A hardware networking component conveying a served page data structure, the data structure specifying a page for rendering and comprising: information specifying each of a plurality of page elements, at least a portion of the plurality of page elements specifying visual features of the page; and information explicitly identifying one or more of the plurality of page elements as being the object of an extraction control to be included in the page when rendered that, when executed, extracts a portion for the page for storage independent of the page, such that, when the data structure is received for rendering, the identified page elements can be extracted in response to activation of the extraction control.