Still confused about $'s before variables in javascript / jquery
<p>In my previous <a href="http://stackoverflow.com/questions/10443463/do-i-need-to-put-a-dollar-before-variable-names-with-javascript">question</a> a poster suggested the following:</p>

<pre><code>var formSubmitHandler = function (link, form) {
    var $form = $(form);
    var val = $form.valid();
    var action = $form.data('action');
    var entity = $form.data('entity');
</code></pre>

<p>I understand now that the $ before is used to show the variable is a jQuery object. My question is Why do I need the line "var $form = $(form)" ?   Could I not just have $form = form?</p>
