Is my page framed?
Question: Is my page framed (loaded in a frameset) or is it in the browser's top-level window?
Answer: To test whether your page is in a frameset, you can use this conditional operator:
Example. Let's assume that your site uses frames to provide some navigation functionality
A similar code is used on this page. If you open this page in the top-level window of your browser, you'll see a hyperlink Contents (at the top of the page, right under the page title). This hyperlink will bring you back to the framed view.