# Identifiers

## Overview

The sections here describe various user identifiers used in MOSIP.

## UIN

Unique Identification Number (UIN), as the name suggests, is a unique number assigned to resident. UIN never changes and is non-revocable. UIN is randomized such that one should not be able to derive any Personal Identifyable Information (PII) from the number itself.

The rules that govern generation of a UIN are listed [here](https://github.com/mosip/commons/blob/1.2.0-rc2/kernel/kernel-idgenerator-service/README.md)

* uin configuration properties
* storage

## VID

## RID

## PRID

## APPID

* What is appid
* What is the relationship of appid, rid, prid (it at all)
* Is appid seen by residents on receipts, email, messages.
* Correction packet. Multiple appids associated with RIDs.

## Token