Aadhaar is the Indian government’s resident identification number system which has registered about 1.2 billion Indians — nearly the entire country. While Aadhaar doesn’t directly relate to internet communications, it is both dependent on and enabling of many online services.

Aadhaar is a random 12 digit number that links to biometric data, typically a photo, ten fingerprints and two iris scans. Soon Aadhaar will include facial recognition services as well.

Registration with Aadhaar is voluntary, but so many government and commercial services are now linked to Aadhaar (welfare programs, pensions, banking services, mobile phone accounts, etc.), Aadhaar is used by essentially everyone in India.

Like any powerful technology, Aadhaar brings both profound advantages and significant risks.

An Aadhaar identification number allows Indian citizens — including its poorest — ready access to information and services heretofore unavailable. It increases efficiency and decreases corruption.

On the other hand, identity services such as this can lead to data breaches, fraud, and abuse.

Many countries are developing or refining their own identification systems. Aadhaar is currently the largest, and in many ways, most impactful personal identification system on the planet.