a method and an apparatus for providing bidirectional communication between a user agent and an internet web server . some applications include user agent initiated on demand access to web content without requiring a web page reload , updating of shopping cart information , extension of displayed product information and tracking of user interaction history . web content can be accessed in response to a user agent detectable event , including such as the selection of a text field or a button . this approach enables user agent resident java script to access and process web content before it is rendered to a user .