title: What is the purpose of FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters) inside Global.asax
body: <p>I have read the similar question<a href="https://stackoverflow.com/questions/5343946/what-is-the-purpose-of-registerglobalfilters">What is the purpose of RegisterGlobalFilter</a></p>
  
  <p>but unable to get the answer, the question somewhat revolves around some other stuff too and the anwser doesn't seems fullfilling to me.</p>
  
  <p>My question is:-
  what is the purpose of this line inside global.asax in MVC 5 <code>FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);</code></p>
  
  <ol>
  <li>Why it is needed ? </li>
  <li>What is the purpose of adding/registering
  filters? </li>
  <li>What does the filter have to do?</li>
  </ol>