title: Does Promise.all() run in sequential or parallel?
body: <p><strong>Does Promise.all() run in sequential or parallel in Javascript?</strong></p>
  <p>For Example:</p>
  <pre class="lang-js prettyprint-override"><code>    const promises = [promise1(), promise2(), promise3()]
      Promise.all(promises)
      .then(data =&gt; {
          // whatever 
      });
  </code></pre>
  <p>Does <code>promise1()</code> execute and resolve before moving onto promise2() or does <code>promise1()</code>, <code>promise2()</code>, and <code>promise 3()</code> all run in parallel at the same time? I would assume like Node, Javascript in the browser to be single threaded thus they don't run in parallel?</p>