In previous lesson we talk about standard event model (EventListener). That is very useful for new major browsers but we are still have a problem, that method (addEventListener / removeEventListener) doesn't support in legacy Internet explorer 8 or below.
For sought out this problem we can use attachEvent method or detachEvent method. Just see an overview on it but it's not so useful, because i think nobody uses in present too old browsers(Internet explore 8 and below). But it can be possible we have to work some day for any client which requirement fulfill with this browser, so we have to know about this method. (attachEvent | detachEvent)Let see.
