Just create a Function in your Script and put part of the Attribute type Event – like onmouseover, onmouseout, onclick, onchange, it can handle the Event that occurs with the DOM.
Function just created in the Script, and placed them as the Attribute Type Event onclick, onmouseover, onmouseout, onchange Event occurs, it can deal with the DOM, it has it.
Just create a Function in parts of the Script and placed parts of the Attribute type Event; such as onclick OnMouseOver onmouseout,,,, Onchange can deal with Event happened to DOM about that now.