title: What is web.xml file and what are all things can I do with it?
body: <p>The <a href="http://docs.oracle.com/cd/E13222_01/wls/docs81/webapp/web_xml.html" rel="noreferrer">web.xml Deployment Descriptor Elements</a> in Oracle's BEA WebLogic Server 8.1 Documentation pretty much sums up each element in a web.xml file. But I am also curious about points below:</p>
  
  <ol>
  <li>Is there any configuration parameter which should be avoided like plague?</li>
  <li>Any parameters related to performance or memory usage?</li>
  <li>Security related risk due to common mis-configuration?</li>
  </ol>
  
  <p>What else should I know about web.xml apart from element names and their usage?</p>