Sree Sankar
This is not what you're hosting on your breakups!
HTML have no relationships! So it is more like actions we users doing by mouse or keyboard; like clicking, mouse-hovering, typing, changing values etc..
Not only because HTML enjoy his life but also HTML has the ability to let events trigger actions in a browser, like starting a JavaScript when a user clicks on an element.
Yaaas!
Mainly we using events are onchange, onclick, onsubmit, onmouseover, onselect and etc