title: what does the hash mean in action="#" in html form tag
body: <p>What does it mean for action="#" in the html form tag.
  For example,</p>
  
  <pre><code>&lt;form action="#" method="post" class="demoForm" id="demoForm"&gt;
  
      &lt;fieldset&gt;
          &lt;legend&gt;Demo: Checkboxes Sharing Same Name&lt;/legend&gt;
  
      &lt;p&gt;Check the types of sports or fitness activities you engage in on a regular basis.&lt;/p&gt;
  
      &lt;p&gt;
          &lt;label&gt;&lt;input type="checkbox" name="sports[]" value="cycling" /&gt; cycling&lt;/label&gt;
          &lt;label&gt;&lt;input type="checkbox" name="sports[]" value="running" /&gt; running&lt;/label&gt;
          &lt;label&gt;&lt;input type="checkbox" name="sports[]" value="other" /&gt; other&lt;/label&gt;
      &lt;/p&gt;
  
      &lt;/fieldset&gt;
  
  &lt;/form&gt;
  </code></pre>