title: How does std::flush work?
body: <p>Can someone please explain (preferably using plain english) how <code>std::flush</code> works?</p>
  
  <ul>
  <li>What is it?</li>
  <li>When would you flush a stream?</li>
  <li>Why is it important?</li>
  </ul>
  
  <p>Thank you.</p>