title: Why a simple <script src="..."> </script> doesn't work?
body: <p>I'm working on a project, and I didn't understand why a call to external script doesn't work.</p>
  
  <p>Then I just did a extremely simple page html which includes a script alert, as you can see below... Can you tell me what's the problem ? I believe the problem is not the code, but what else can it be?</p>
  
  <p>My browser is a recent Chrome, and my OS is Ubuntu.
  My HTML file is index.html :</p>
  
  <pre><code>&lt;!DOCTYPE html&gt;
  &lt;html&gt;
  &lt;head&gt;
  &lt;meta charset="utf-8"&gt;
  &lt;meta http-equiv="X-UA-Compatible" content="IE=edge"&gt;
  &lt;title&gt;MyPage&lt;/title&gt;
  &lt;/head&gt;
  &lt;body&gt;
      &lt;p&gt;Blablabla&lt;/p&gt;
      &lt;script type="text/javascript" src="/script.js"&gt;&lt;/script&gt;
  &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>
  
  <p>The Javascript file is script.js in the same folder:</p>
  
  <pre><code>&lt;script type="text/javascript"&gt;
  alert('Hey');
  &lt;/script&gt;
  </code></pre>