Standard forwarding is a type of domain parking which enables you to specify an URL to handle requests to your parked domain. Thus, an HTTP request to your parked domain will be redirected to the specified URL. The HTML document will be located at this URL.
Suppose, you have a parked domain www.mydomain.com. You want the visitors of www.mydomain.com to see a page located at www.forward.com. For this case, you should select standard forwarding as a type of parking.