The Unique Identification Authority of India (UIDAI) - under the chairmanship of Nandan Nilekani - is the nodal agency, which had appointed registrars across the country to facilitate the enrolment process.

Nilekani was one of the co-founders and previously headed IT bellwether Infosys. He enjoys cabinet rank in his present status.

Registrars are typically government departments and public sector organisations. They in turn appoint the agency to collect data. Currently, over 200 such agencies have been named including Wipro, Comat Technologies, Alankit and Virgo Softech.

"Aadhaar guarantees uniqueness and a universal identity. At its core is a centralised online identity verification process," said Atul P. Anand, director at Virgo Softech, which is one of the enrolment agencies involved in the process.

"Biometric information like iris and fingerprints ensure this uniqueness. This is also embedded and hence tamper proof. The authority uses data de-duplication process, which also makes sure that only unique data is stored," Anand told IANS.

Officials explained the enrolment is done in four stages -- verification of documents including address proof, on-the-spot capture of photos, iris and fingerprint scanning -- after which people are given acknowledgment slips at the time of enrolment.

A 12-digit unique identification number is then delivered in 20-30 days at the person's address through speed post after verification of biometrics and demographic data. Data verification is done by the authority under a centralised system.

The system ensures duplicate data is deleted, leaving only one copy to be stored.
"If you try to enrol yourself for the second time by using some different demographic information or data, you cannot do it. That's also because you can't change your iris and fingerprint. So duplicate data automatically gets deleted," said Anand.

There is also no age bar to enrol for the number.But the unique number of a child up to five years of age is linked to that of his or her parents or guardians. On completion of 15 years of age, biometric data is updated, but the number remains the same.

The people who don't remember their date of birth and have no documents to back it can provide approximate age. Transgenders have also been included; so under gender options, there are three categories -- male, female and transgenders.

"The number can be issued to even a new-born and it remains the same throughout the life. The system is also versatile. Both biometric and demographic data can be updated," a Virgo official said. But the authority has not started the updation process.
On concerns over security and privacy issues, officials said it was, indeed, a rather big challenge and that the authority was trying to make sure that the unique identity number is not misused.

Many analysts have raised concerns that the number can be misused by anti-socials such as terrorists, since they can get it issued through fake identities during large-scale enrolments.

And once it is issued, a person can easily apply for a passport and open bank accounts.
The authority issued the Aadhaar number in September 2010 and targets 600 million people over the next four years. It has to issue every resident a unique identification number that can be used to establish the identity of the person anywhere in India.
Currently, on an average 150,000 enrolments are done each day. The number of enrolments is expected to reach six million per day by October. The task, therefore, is daunting, since the latest data places the country's population at 1.21 billion.

 Some frequently asked questions answered on "Aadhaar":

What is Aadhaar:
A tool for social empowerment and inclusion, Aadhaar is a 12-digit number being issued to all residents by the Unique Identification Authority of India (UIDAI). This number is stored in a central database and linked to some basic demographics and biometric information -- photo, 10 fingerprints and iris -- of each individual.

Why Aadhaar:
For applicants, Aadhaar, over time, will be recognised and accepted across the country and become the basic, universal identity of residents for all public and private services. Once enrolled, service providers will no longer face the problem of performing repeated 'know your customer' checks.

Genesis of Aadhaar:
Inability to prove one's 'identity' is one of the biggest barriers preventing the poor from accessing benefits and subsidies given by the government or private agencies. Aadhaar promises an identity to every resident - children, differently-abled people, tribespeople, unorganised workers, the poor and the marginalised can also secure a unique identity.

Who can get Aadhaar:
Every individual, from infants to seniors, who is a resident in India and satisfies the verification process laid down by the Authority can get an Aadhaar.

How to Get Aadhaar:
The resident needs to go to the nearest enrolment camp and register for an Aadhaar, along with certain specified documents. Upon registering, residents will go through a biometric scanning of 10 fingerprints and iris. They will then be photographed. The 'Aadhaar' number will be issued within 20-30 days.

How to track Aadhaar application:
Every resident seeking enrolment is given a printed acknowledgment form with an enrolment number that enables her/him to make queries through any of the communication channels - phone, fax, letter or e-mail.

What use can Aadhaar be put to:
Aadhaar means foundation. It can be used in any system that needs to establish the identity of a person seeking a service. It will particularly help the delivery of programmes on food and nutrition, employment, education, inclusion and social security, healthcare, and other services such as property transactions, election card, tax card and driving licence.