1// 1. Using console.log()
2console.log("Hello World");
3// console.log() is used in debugging the code.
4
5// 2. Using alert()
6alert("Hello, World!");
7// // The alert() method displays an alert box over the current window with the specified message.
8
9// 3. Using document.write()
10document.write("Hello, World!");
11// // document.write() is used when you want to print the content to the HTML document.

1// Output Hello World! in the console.
2console.log("Hello World!");

1I would do something like this:
2
3<script>
4  alert("Hello World!");
5</script>
6

1console.log("Hello World!");

1alert("Hello world");

1// the hello world program
2console.log('Hello World');