If you push the "play" button, the orange point will start to move from left to right along the Cartesian plane, i.e., increasing values for the x coordinate.[br]You can move the orange point up and down on the blue line.[br]Every time you do so, you will get the graphic of a function.[br]Push "restart" to begin a new graphic ([b]CONTROL+F[/b] resets the graphic view)