how to connect a js file in html

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

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

1<script src="index.js"> </script>
2

1<!--if you save the javascript file in a folder-->
2<script type="text/javscript" src="foldername/filename.js"></script>
3<!-- If you save the file in the parent folder-->
4<script type="text/javscript" src="filename.js"></script>