title: When to use ' (or quote) in Lisp?
body: <p>After making it through the major parts of an introductory Lisp book, I still couldn't understand what the special operator <code>(quote)</code> (or equivalent <code>'</code>) function does, yet this has been all over Lisp code that I've seen.  </p>
  
  <p>What does it do?</p>