A system for initiating an action in a processing system. The system comprises a printed page having an interactive element enabling user interaction with the page; an optically imaging sensing device for interacting with the interactive element and generating indicating data using sensed coded data; and a processing system configured for: receiving the indicating data, identifying a page description corresponding to the printed page; identifying the interactive element and initiating an action associated with the interactive element. The printed page comprises a plurality of coded data portion, each containing a code pattern encoding a unique location on the page and identifying a page identity.