title: Meaning of nonprintable characters
body: <p>Sometimes, when I accidentally route nonprintable characters to the console, I get little boxes with 0's, 1's and other things in them.  </p>
  
  <p>What is the meaning of these boxes?<br>
  What is the meaning of the 0's and 1's?<br>
  Why show the characters this way?</p>
  
  <p><img src="https://i.stack.imgur.com/w5dxY.png" alt="Example nonprintable characters"></p>