Check out example codes for "include script in html". It will help you in understanding the concepts better.

Code Example 1

<script type="text/javascript" src="yourfile.js"></script>

Code Example 2

<script src="index.js"></script>

Code Example 3

<script type="text/javascript" src="/path/to/script.js"></script>

Code Example 4

<script type="text/javascript" src="path-to-javascript-file.js"></script>

Code Example 5

<script src="Your-JavaScript-File.js"></script> <!--If JS file is in same folder with HTML file-->

Code Example 6

<script src¨script.js¨></script>

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