Let's say you have registered mydomain.com.au and you have set up URL forwarding to point to http://myisp.com.au/myuser/mypage.htm. 

When URL forwarding is active and someone types in www.mydomain.com.au into their web browser, they will be redirected to your web page hosted elsewhere however in the address bar all they will see is www.mydomain.com.au at all times while they are viewing your page until they click on a link away from your page.

This process is commonly referred to as URL cloaking.