title: Google Analytics tracking code in external JS File
body: <p>I add Google Analytics tracking code to my website.  </p>
  
  <p>How do I make an external JS and link that to all of my web pages?</p>
  
  <pre><code>(function(i, s, o, g, r, a, m) {
      i['GoogleAnalyticsObject'] = r;
      i[r] = i[r] || function() {
          (i[r].q = i[r].q || []).push(arguments)
      }, i[r].l = 1 * new Date();
      a = s.createElement(o),
          m = s.getElementsByTagName(o)[0];
      a.async = 1;
      a.src = g;
      m.parentNode.insertBefore(a, m)
  })(window, document, 'script', '//www.google-analytics.com/analytics.js', 'ga');
  </code></pre>