title: Why do Facebook Insights and Google Analytics report different visitor counts?
body: <p>I'm using both on a site and getting very different numbers from each. Why is this? </p>
  
  <p>The discrepancy is also mentioned in a Quora answer (<a href="http://www.quora.com/Which-is-better-Facebook-Insights-or-Google-Analytics" rel="nofollow">Which is better, Facebook Insights or Google Analytics</a>?)</p>
  
  <blockquote>
    <p>Footnote: if you decide to use both, do not report them side-by-side,
    and never expect them to match. Trying to explain the differences will
    drive you mad.</p>
  </blockquote>
  
  <p>Could someone explain?</p>