title: What is Java Message Service (JMS) for?
body: <p>I am currently evaluating JMS and I don't get what I could use it for. </p>
  
  <p>Currently, I believe this would be a Usecase: I want to create a SalesInvoice PDF and print it when an SalesOrder leaves the Warehouse, so during the Delivery transaction I could send a transactional print request which just begins when the SalesOrder transaction completes successfully.</p>
  
  <p>Now I found out most JMS products are standalone server. </p>
  
  <ul>
  <li>Why would a need a Standalone Server for Message Processing, vs. e.g. some simple inproc processing with Quartz scheduler? </li>
  <li>How does it interact with my application? </li>
  <li>Isn't it much too slow? </li>
  <li>What are Usecases you already implemented successfully?</li>
  </ul>