A national identifier is a unique number assigned by a government to its citizens,
residents, or eligible individuals for identification purposes. It can be used to track
individuals for things like taxation, social security, healthcare, and other official
functions.
The type of national identifier required for
identification and verification varies significantly from country to country. Some
countries rely on national identity cards, while others use social security numbers
(SSN), tax identification numbers, passport numbers, or other government-issued
documents. For example, the United States can use SSN and driver’s license. For the
United Kingdom, it can be passport and driver’s license.