You can also use the X-Frame-Options HTTP header. This header tells a web browser whether or not to allow a web page to be framed in another web page. This includes
There are two possible values for this header:
DENY - This setting prevents any pages served from being placed in a frame even if it is on the same website it originates from. should be used if you never intend for your pages to be used inside of a frame.
SAMEORIGIN - This setting allows pages to be served in a frame of a page on the same website. If an external site attempts to load the page in a frame the request will be denied.
This header works in Internet Explorer 8.0, Firefox 3.6.9, Opera 10.50, Safari 4.0, and Chrome 4.1.