JavaScript Alert pop up

By window. Alert property we can show a alert box on html page. Without click on that box  we can not do anything on html page.

<h1>Using window.alert()</h1>

<script>

window.alert("hello its javascript. click to ok");

</script>

go  to this link and see the live demo.

https://jsfiddle.net/ssgp6mwr/11/