Webpage menu - Listbox

I'm new to java or javascript whichever I will need to do this. How would I make a simple menu with text

Downloads
Forum
Chat

like that and when the user clicks a section it acts like a listbox in windows sort of.

Downloads
Section1
Section2
Forum
Chat

So it like drops down and when the user clicks downloads again it goes back to normal (the beginning). I'm doing this for a menu of a webpage so if anyone can help me out id appreciate it cause i dont have the slightest clue. thanks for everyones helps, if anyone has questions please ask!

So you mean like a tree menu, but with a list box?