How to make the most basic show hide div in javascript?

Question

I want to make a very simple dropdown menu which I will style with CSS. How do I make the menu show when either a div or a link or anything is rolled over and how do I make it hide when rolled out.

Do you know anything mega basic so I can see what all the code is doing if possible.

Answer 1

You can swipe my code from:

http://home.comcast.net/~richarduie/web-...

You can use the YUI prototypes at:

http://developer.yahoo.com/yui/menu/

My code's simpler - the YUI is more rich in features.