jQuery .length() speed implications
<p>Whenever I want to find if an element exist in the DOM I use the following code.</p>

<pre><code>if($('#target').length){
    // do stuff.
}
</code></pre>

<p>This works well and I use it quite a lot on client sites.</p>

<p>Question:
How fast is this method? What are the speed implications when this is used a lot in a project? </p>
