Authorization is a process of allowing or denying resources to particular user or record 

Declaration of authorization is 

<authorization>
<allow users=”Suresh, Sanjay”/>
<deny users=”Ramana, Rakesh”>
</authorization>
Sometimes authorization allows the unauthorized persons at
that time we will use
<deny users=”?”/>

Authentication means 

Authentication is a process where we identify the credentials of user i.e. username, password and create an identity to mention user as an authenticated.