WordPress will generally inject jQuery into your front-end theme which in my opinion is a huge fail. Often times plugins will do it, fortunately there is a simple fix, just above wp_head() or inside of an init callback put:
<?php if ( !is_admin() ) wp_deregister_script('jquery'); ?>
jQuery won’t be linked anymore. Writing this post has made me start wondering if I should write a more detailed post about WP_Scripts to show how to create dependancies and registering your own scripts. Any interest?