title: Can someone explain Navigator Class and Scaffold Class from Flutter?
body: <p>The Flutter documentation is so vague. Can you guys explain what Google is vaguely saying:</p>
  
  <p><strong>Navigator Class</strong></p>
  
  <blockquote>
    <p>Many apps have a navigator near the top of their widget hierarchy in order to display their logical history using an Overlay with the most recently visited pages visually on top of the older pages.</p>
  </blockquote>
  
  <ol>
  <li>What does it mean "near the top [...] in order to display their logical history"?</li>
  <li>what does it mean by "logical history"?</li>
  </ol>
  
  <p><strong>Scaffold Class</strong></p>
  
  <blockquote>
    <p>Implements the basic material design visual layout structure. </p>
  </blockquote>
  
  <ol>
  <li>Why is the Scaffold class implementing material design? Isn't that the job of the MaterialApp class? </li>
  </ol>