title: I get an error when I declare a new variable in the function argument : Why is that?
body: <p>For a function with an argument :</p>
  
  <pre><code>function displayCouplet(var couplet) {
     document.write(couplet);
  }
  
  displayCouplet("The object of my worship lies beyond perception's reach,For men who see, the Ka'aba is a compass, nothing more.");
  </code></pre>
  
  <p>displays an error <em>Uncaught SyntaxError: Unexpected token var</em> . Why is that ? If I omit the keyword <code>var</code> from the argument,then it goes fine. Please explain why is this ?</p>