<!DOCTYPE html>
<html>
<body>
<p>This example uses the addEventListener() method to execute a function when a user clicks on a button.</p>
<button id="myBtn">Try it</button>
<p id="demo">
<script>
document.getElementById("myBtn").addEventListener("click", myFunction);
function myFunction() {
document.getElementById("demo").innerHTML = "Hello World";
}
</script>
</body>
</html>