One of the most annoying things websites do to display a page from your site in a
frame. Here's an easy way to fix it.
Google Images, besides
to get rid of the frame and reload the page to its proper URL:
if (top != self)
refers to the current window; "top" is a reference to the top-level
window which should contains the current window in a "frameless" setting.
Otherwise, somebody is framing you. If you feel like an evangelist, you could
feel free to replace location.href with a URL to some page which extolls the
virtues of being a good netizen.