title: Ruby: Curious usage of "?" operator in comparing strings for equality
body: <p>I found code similar to below in <code>ftp.rb</code> file.
  I am wondering what is the use of <code>?</code> in the below example.  I know it is checking for equality, but never seen such a syntax</p>
  
  <pre><code>p "-" == ?-  # Prints true
  p "a" == ?-  # Prints false
  </code></pre>