title: Node.js - Async.js: how does parallel execution work?
body: <p>I want to know how parallel execution works in async.js</p>
  <pre><code>async = require('async')
  
  async.parallel([
      function(callback){
          for (var i = 0; i &lt; 1000000000; i++) /* Do nothing */;
          console.log(&quot;function: 1&quot;)
      },
      function(callback){
          console.log(&quot;function: 2&quot;)
      }
  ]);
  </code></pre>
  <p>In the above example, I expect obtain the output:</p>
  <blockquote>
  <p>function: 2</p>
  <p>function: 1</p>
  </blockquote>
  <p>but, the console throws the inverse, what is happening? thanks.</p>