Attribute for <IFRAME ...>
FRAMEBORDER =1 |0

FRAMEBORDER indicates if the inline frame should have a border around it. 1 (the default) indicates it should, 0 indicates it should not.

this code	produces this
<IFRAME SRC="BeaverHabitat.html" WIDTH=150 HEIGHT=150 FRAMEBORDER=0 > <A HREF="BeaverHabitat.html">Stuff about the Beaver</A> </IFRAME>
<IFRAME SRC="BeaverHabitat.html" WIDTH=150 HEIGHT=150 FRAMEBORDER=1 > <A HREF="BeaverHabitat.html">Stuff about the Beaver</A> </IFRAME>
<IFRAME SRC="BeaverHabitat.html" WIDTH=150 HEIGHT=150> <A HREF="BeaverHabitat.html">Stuff about the Beaver</A> </IFRAME>		(don't use FRAMEBORDER at all )

<IFRAME MARGINWIDTH="..."> >>>