What does $("something") in javascript mean?
<blockquote>
  <p><strong>Possible Duplicate:</strong><br>
  <a href="http://stackoverflow.com/questions/1150381/what-is-the-meaning-of-sign-in-javascript">What is the meaning of &ldquo;$&rdquo; sign in javascript</a>  </p>
</blockquote>



<p>This may be a basic question, but I dare ask.</p>

<p>While I was navigating javascript codes, I found the following.</p>

<pre><code>    if(selected_len == all_len) {
        $(":checkbox:checked.node_id_"+d.nodeValue).click();
    }
</code></pre>

<p>I tried to search what $("") means, but all I found is </p>

<p>"$('hello') --- This is a function declared by many JavaScript frameworks as an extension of document.getElementById."</p>

<p>Could you give more precise explanation, as if you talk to a child :)</p>
