What are action filters in asp.net mvc?

Action filters are attributes that can be applied either on a controller action method or on a controller. When applied at the controller level, they are applicable for all actions within that controller. Action filters allow us to add, pre and post processing logic to an action method. This means, they allow us to modify the way in which an action is executed.

Authorize  ChildActionOnly HandleError OutputCache  RequireHttps ValidateInput ValidateAntiForgeryToken