Filters are pieces of logic that can be attached over controllers or actions which affects the way in which a request get processed. Filters are normally used to perform the common functionalities in an application like authorization, caching and logging. Filters can be applied over actions, controllers or at global level. When the filters are applied at global level they affect all the actions of all controllers. In this article we will learn about the basic things of filters, types of filters, creating custom filters and more.