title: web application for data modeling
body: <p>I am about to start development of a web based application and we need to create a data model for that.</p>
  
  <p>Is there any </p>
  
  <ul>
  <li><strong>web based</strong> </li>
  <li><strong>free</strong> and ready to go</li>
  <li>or <strong>open source</strong> so I can install it on my linux server</li>
  <li>that allows <strong>collaboration</strong></li>
  </ul>
  
  <p>application for <strong>data modeling</strong>? </p>