title: How is it possible for an iframe to access its parents DOM?
body: <p>How is it possible for a script within an <code>&lt;iframe&gt;</code> to have any notion of the page containing it? Can a script in the frame access any context outside of it? What about cross-domain?</p>
  
  <p>Up until now I believed an <code>&lt;iframe&gt;</code> is <em>completely</em> agnostic to the containing page, but I have seen an example which contradicts this belief.</p>
  
  <p>What exactly can and can't be done from within an <code>&lt;iframe&gt;</code> with respect to the containing page?</p>