importar js en html
<script type="text/javascript" src="yourfile.js"></script>
SteDeus
<script type="text/javascript" src="yourfile.js"></script><script src="index.js"></script> <script type="text/javascript"
src="file.js">
</script> <html>
<head>
</head>
<body>
<script type="text/javascript" src=es4.js></script>
</body>
</html>
<script type="text/javascript" src="path-to-javascript-file.js"></script><script type="text/javascript" src="path/filename.js"></script>