The best first step to improving the JavaScript performance of your web site is to simply include the latest version of jQuery, as every new release brings more optimizations and bug fixes. Requesting jQuery from a CDN is also a good choice, as it will minimize the loading time of your site (a CDN is faster to serve the library, and many people …

jQuery 1

<!-- jquery-cdn-js.html-->

<!-- Case 1 - requesting jQuery from the official CDN -->
<script src="http://code.jquery.com/jquery-1.10.2.min.js"></script>

<!-- Case 2 - requesting jQuery from Googles CDN (notice the protocol) -->
<script src="//ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js"></script>

<!-- Case 3 - requesting the latest minor 1.10.x version (only cached for an hour) -->
<script src="//ajax.googleapis.com/ajax/libs/jquery/1.10/jquery.min.js"></script>

<!-- Case 4 - requesting the absolute latest jQuery version (use with caution) -->
<script src="http://code.jquery.com/jquery.min.js"></script>