Sliding Menu (on Mouse Over)
One of the major features of AllWebMenus, included in the "Type" group property, is the ability to set a menu subgroup to appear as a sliding submenu (see also "Sliding Menu" in examples list).
In this particular example, the "Company" and "About" submenus slide below their parent item and extra "Indentation" and "Margin" are in use to make the submenus smaller in width.
The difference between this example and the regular "Sliding Menu" example is that all submenus slide when the mouse hovers their parent item (instead of a mouse click event).
This is helpful even in a menu with both sliding and drop-down in action since you can keep a common behavior and force all submenus to appear either on Mouse Over or Mouse Click events.
More info on Sliding Menu Add-in
Example I Example II Example III
this AllWebMenus project file.