Vertical Mega Menu With Hover Delay The hover delay is one of the most important features in any themes using vertical category menus, and extremely useful for user experience. What are HTML Helpers in MVC? HTML Helpers are like controls in traditional web forms. Which are the important namespaces used in MVC? Below are the important namespaces used in MVC — MVC MVC.Ajax MVC.Html MVC.Async What is ViewData?