Why use Gtk2::Bin ?

[zentara <zentara zentara net>]

Hi,
I was just going through the great study-guide by
Dirk van der Walt   at
http://forge.novell.com/modules/xfcontent/downloads.php/exam/documentation/

He makes a big point about the object heirarchies.

I was just wondering, why are Windows and Buttons
derived from Gtk2::Bin  instead of Gtk2::Box?

Does it make them more efficient?


-- 
I'm not really a human, but I play one on earth.
http://zentara.net/japh.html