title: purpose of webAppRootKey?
body: <p>Can somebody explain this entry in web.xml ? When it has to be used and why ?</p>
  
  <pre><code>&lt;context-param&gt;
      &lt;param-name&gt;webAppRootKey&lt;/param-name&gt;
      &lt;param-value&gt;webapp.root&lt;/param-value&gt;
  &lt;/context-param&gt;
  </code></pre>
  
  <p>Is this something related to Spring or general one?</p>