YUI recommends YUI 3.
YUI 2 has been deprecated since 2011. This site acts as an archive for files and documentation.
The Menu family of components features a collection of controls that make it easy to add menus to your website or web application. With the Menu Controls you can create website fly-out menus, customized context menus, or application-style menu bars with just a small amount of scripting.
The Menu family of controls features:
This module contains the following classes: