This worksheet demonstrates how points can automatically be moved on various geometric objects using the [url=http://wiki.geogebra.org/en/Point_Command]Point[Object, Parameter] command[/url], where [i]Parameter[/i] is a value between 0 and 1.
It also demonstrates how you can get the path parameter from an object which can be moved by the user, using the [url=http://wiki.geogebra.org/en/PathParameter_Command]PathParameter[Point] command[/url].