title: What is a python thread
body: <p>I have several questions regarding Python threads.</p>
  
  <ol>
  <li>Is a Python thread a Python or OS implementation?</li>
  <li>When I use htop a multi-threaded script has multiple entries - the same memory consumption, the same command but a different PID. Does this mean that a [Python] thread is actually a special kind of process? (I know there is a setting in htop to show these threads as one process - <code>Hide userland threads</code>)</li>
  <li><a href="http://docs.python.org/library/threading.html#thread-objects" rel="noreferrer">Documentation</a> says:</li>
  </ol>
  
  <blockquote>
    <p>A thread can be flagged as a “daemon thread”. The significance of this
    flag is that the entire Python program exits when only daemon threads
    are left.</p>
  </blockquote>
  
  <p>My interpretation/understanding was: main thread terminates when all non-daemon threads are terminated.</p>
  
  <p>So python daemon threads are not part of Python program if "the entire Python program exits when only daemon threads are left"?</p>