What is uid? What is auth? What is a verifier?

What is? uid？
UID, User identification （User Identification） Abbreviation , The value automatically generated by the system when the network platform is registered .
What is? Auth?
Its identity , Compare boss staff The manager .....
This function is used to distinguish different permissions . For example, the boss has all the permissions of the software . Employees have only part of the authority
What is a verifier ？
It is a custom class