title: Android -Activity - Thread Basics
body: <p>I am still confused at threads. Still I could see some answers which points to threads, UI thread, background thread, main thread etc. (mostly on AsyncTasks and updating UI from  background threads etc.) </p>
  
  <p>Could anyone give me a complete explanation around these or some links at least? </p>
  
  <p>It would be great if the answer covers the following cases:</p>
  
  <p><strong>Which are all the threads that's involved:</strong></p>
  
  <ul>
  <li>When I am running an activity (setting the content view, attaching some buttons, some dialog messages)</li>
  <li>An activity with AsyncTask</li>
  <li>A Background Service </li>
  <li>A HTTP call</li>
  </ul>