<frame name="topFrame" src="top.html">

<a href="javascript:alert(self.location)">what is my source document?</a>

<a href="javascript:alert(parent.location)">what is my parent's source document?</a>

<a href="javascript:alert(top.location)">what is top's source document?</a>

<a href="javascript:alert(parent.leftFrame.location)">what is leftFrame's source document?</a>

<a href="javascript:alert(parent.leftFrame.document.forms[0].elements[0].value)">what is leftFrame's document's form element's value?</a>