This script checks to see if the user is comming from the right url(s). If the user visits the page from the wrong url(s), an alert will popup, then it will try to close the window (if it is a popup, it will automaticly close, if it is a regular window, a promt will come up asking if the user wants to close the window or not), then, if the window is not closed, it will make the window go back a page.