A system for enabling user interaction with computer software which includes a computer system which transfers print data to a printer which is responsive to the print data to print a form by printing information indicative of a text field coincident with coded data at least partially indicative of the text field, so that when a sensing device is moved in an operative position relative to the text field, the sensing device can sense the coincident coded data and generate the indicating data indicative of movement of the sensing device relative to the text field. The computer system uses the indicating data to determine the movement and then perform an action associated with the text field based on the movement. The computer system determines a handwritten signature using the movement and a predetermined signature using a user identity, and verifies the user by comparing the handwritten and predetermined signatures.