Referring Url Probe is a multi-platform compatible script that can help keep visitors on your web site longer, especially if you have reached a targeted visitor. How is this possible? The Referring URL Probe control determines if a visitor has accessed one of your web pages directly, or through another site (such as a search engine). If the control detects that the visitor has directly accessed a web page, or has come from another site, it will display a timed message that the visitor will see. Otherwise it will not activate itself.