title: OSGi: What are the differences between Apache Felix and Apache Karaf?
body: <p><a href="http://karaf.apache.org" rel="noreferrer">Apache Karaf</a> is a sub project of <a href="http://felix.apache.org/" rel="noreferrer">Apache Felix</a>. It is defined as "a lightweight OSGi container".</p>
  
  <p>I don't understand when should I use the heavyweight and when to use the lightweight. Their site doesn't explain this too much.</p>