The Unique Identification Authority of India (UIDAI) was set up by the Government of India in January 2009,as an attached office under aegis of Planning Commission vide its a gazette notification. The UIDAI is mandated to assign a 12-digit unique identification (UID) number (termed as Aadhaar) to all the residents of India. As per the notification, the UIDAI has been given the responsibility to lay down plan and policies to implement UID scheme, to own and operate the UID database and be responsible for its updation and maintenance on an ongoing basis. The implementation of UID scheme entails generation and assignment of UID to residents; defining mechanisms and processes for interlinking UID with partner databases; operation and management of all stages of UID life cycle; framing policies and procedures for updation mechanism and defining usage and applicability of UID for delivery of various services among others. The number is linked to the resident's basic demographic and biometric information such as photograph, ten fingerprints and two iris scans, which are stored in a centralised database.
The UIDAI data center is located at Industrial Model Township (IMT) Manesar in Haryana state.
Starting with issuing of first UID in September 2010, the UIDAI has been targeting to issue UID - a unique 12 digit Aadhaar number to all the residents that (a) is robust enough to eliminate duplicate and fake identities, and (b) can be verified and authenticated in an easy and cost-effective way online anywhere, anytime.The Government of India in a notification dated 16 December 2010 recognizes the letter issued by Unique Identification Authority of India (UIDAI) containing details of name, address and Aadhaar number, as an officially valid document. It neither aims to replace any existing identity cards nor it is a cognizance of citizenship. Aadhaar neither confers citizenship nor guarantees rights, benefits, or entitlements. Aadhaar is a random number which never starts with a 0 or 1, and is not loaded with profiling or intelligence into identity numbers that makes it insusceptible to fraud and theft. The unique ID would also qualify for as a valid ID while availing various government services, like a LPG connection or subsidised ration or kerosene from PDS or benefits under NSAP or pension schemes, e-sign, digital locker Universal Account Number (UAN) under EPFO and for some other services, like a SIM card or opening a bank account. According to the UIDAI website, any Aadhaar holder or service provider can verify an Aadhaar number for its genuineness through a user-friendly service of UIDAI called Aadhaar Verification Service (AVS) available on its website. Also, a resident already enrolled under National Population Register is not required to enrol again for Aadhaar.