what is the use of script tag in html

1<script type="text/javascript">
2  /*Detects that you are using javascript or text*/
3</script>

1<script>
2	// Put JavaScript inside here
3</script>
4<!-- OR -->
5<script src="all-js/01001/015.js"></script>

1<script type="text/javascript">
2	console.log("text console log");
3</script>

1<script>
2  // Write JS here
3</script>
4
5<script src="link/to/js/file.js"></script>

1<script>
2  //Insert JS scripts here
3  var html
4  html = "You can use the <script> tag to incorporate JS code into your HTML code"
5  console.log(html)
6</script>