Check out example codes for "corona.html:61 Uncaught ReferenceError: $ is not defined". It will help you in understanding the concepts better.

Code Example 1

<script language="JavaScript" type="text/javascript" src="/js/jquery-1.2.6.min.js"></script>
<script language="JavaScript" type="text/javascript" src="/js/jquery-ui-personalized-1.5.2.packed.js"></script>
<script language="JavaScript" type="text/javascript" src="/js/sprinkle.js"></script>

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