title: Difference between d3.event.x and d3.mouse(this)
body: <p>I know that <code>d3.mouse(this)</code> is used to get the mouse coordinates.</p>
  
  <p>Example: </p>
  
  <pre><code>var coordinates = [0, 0];
  coordinates = d3.mouse(this);
  var x = coordinates[0];
  var y = coordinates[1];
  </code></pre>
  
  <p>but what is <code>d3.event.x</code> and <code>d3.event.y</code> used for? I went through the docs which lookslike greek and latin to me</p>
  
  <p>Can any one please explain differences as well? Thanks</p>