Possible Duplicate:
How to prevent my site page to be loaded via 3rd party site frame of iFrame
How to Block Iframe call
I don't want other website use my website content by iframe
Possible Duplicate:
How to prevent my site page to be loaded via 3rd party site frame of iFrame
How to Block Iframe call
I don't want other website use my website content by iframe
Use X-Frame-Options response header, this will tell the browser wether it should show the webpage in a frame or not. E.g.
X-Frame-Options: SAMEORIGIN