Can somebody describe "onload "and"onunload"?

Answer 1

The onload function is called once the browser has fully loaded the web page (HTML document) and populated the DOM. The onunload function is called once the DOM is unloaded from the browser (for example when you leave the page by clicking on a link or closing the browser).

Answer 2

@SamualTees I think you should not use html tag for comments, inside script tag. for more information you can use chrome console. This will let you know where is an error.