title: byte string vs. unicode string. Python
body: <p>Could you explain in detail what the difference is between byte string and Unicode string in Python. I have read <a href="http://www.coolinterview.com/interview/5512/">this</a>:</p>
  
  <blockquote>
    <p>Byte code is simply the converted source code into arrays of bytes</p>
  </blockquote>
  
  <p>Does it mean that Python has its own coding/encoding format? Or does it use the operation system settings?
  I don't understand. Could you please explain?
  Thank you!</p>