JavaScript code can be written in any notepad and saved with a .js extension – you can also embed the code in an html page using the <script>…</script> tags in both the head and body sections. It is better to insert the body into the body of the site, this will speed up the loading of the content of the site itself.
Thus, you can create a file on your computer with the html or htm extension, in which you can prepare the following code:
<html>
<script>
your JavaScript code
</script>
</html>
After saving this file on your computer, you can then open it in any browser and see the result of JavaScript programming. There is an option to access an external file with this code in JavaScript code through the src operator:
<script src=”filename”></script>
Files can be located anywhere, either on the same server or domain, or on the local machine in any folders. The path to the file is set through its full location, you can set the path through the URL so that the script downloads the file with the code from anywhere on the Internet.