What is the difference between permission, rights and policy ?

Permissions - An Administrator of a network or computer system(s) has the abilty to grant permissions to such things as files

User Rights - As an Administrator you can determine wich user has the right to access those devices.

According to me:

Permission as related to access files, folders and even on mailboxes

Rights is related how the user is going to access the resources

Policy is something which is defined by organization and deployed for there resources and objects

Simple it is. Permission is the authority to grant something like attributes for a file or a user. Rights is something the user is permitted to do. Hope you are clear