title: JavaScript Nesting For Loops
body: <p>I have the following code where I fail to understand some parts: </p>
  
  <pre><code>var arr = [
  [1,2], [3,4], [5,6]
  ];
  for (var i=0; i &lt; arr.length; i++) {
   for (var j=0; j &lt; arr[i].length; j++) {
    console.log(arr[i][j]);
    }
  }
  </code></pre>
  
  <p>What does arr[i] mean? I have been told that arr[i] itself is an array. How is that? And What is happening in the arr[i][j] part?</p>