button in top right of applications which hides the menu

Folks,

I am a recent convert to Mac from PC and I am slowly getting to grips with the keyboard short cuts.

One button which I would like to access is the oblong button at the top right of most applications (itunes excluded) which hides the menus leaving just the traffic light viewable.

Does anyone know what it is called and better still how do i access it from the keyboard?

thanks john

For Finder windows you can use ⌥⌘T (Option-Command-T) to hide the toolbar and go into "Old Finder Mode". Use the same key-combo to show the toolbar again. This omnly works with Finder windows as far as I can tell. With most other apps it seems to bring up the character viewer or has no effect. I'm am not sure if it is possible to do it with a keyboard shortcut in anything other than Finder.