The author notes, "The JavaScript confirm alert box differs from a regular alert box in that it provides two choices for the user, OK and Cancel. Typically, you’ll see confirmation boxes utilized on links where the destination is outside the domain of the page you’re currently on or to alert you of potentially objectionable material. The following example will display a confirmation alert box when either a link or form button is clicked. Once either OK or Cancel are selected an alert box will follow to display which was chosen."