Launched in 2009 by the UPA-government under the jurisdiction of the Ministry of Electronics and Information Technology, there are 1.21 billion Aadhaar holders as of May 28, 2018, according to UIDAI. Aadhaar Card as described by World Bank Chief Economist Paul Romer is the most sophisticated ID programme in the world. What is Aadhaar Card? Aadhaar is the world's largest biometric id program and is a 12-digit unique number which is issued by the Unique Identification Authority of India (UIDAI). UIDAI takes an individual's biometric details such as fingerprints and iris scan, and demographic information like address and date of birth before issuing a unique number to an individual. Supreme Court earlier this year, had said in a ruling that it is mandatory to link Aadhaar to open bank accounts and SIM cards. Also, Aadhaar makes it easier for individuals to get their Income Tax returns (ITR) verified. Lost Aadhaar? Don't worry. Go to and download your Aadhaar again. You can also visit any nearby Aadhaar centre and use the 'Find Aadhaar' service to retrieve your Aadhaar.#GetAadhaar pic.twitter.com\/YefeEGmS56 \u2014 Aadhaar (@UIDAI) June 12, 2018 What if you lose your Aadhaar Card? Need not worry. According to a tweet by UIDAI, a person can get his\/her Aadhaar just by sitting at home. All they have to do is visit 'resident.uidai.gov.in UIDAI tweeted: "Lost Aadhaar? Don't worry. Go to and download your Aadhaar again. You can also visit any nearby Aadhaar centre and use the 'Find Aadhaar' service to retrieve your Aadhaar." Here are the steps to download Aadhaar card: Step 1: Click on the mentioned link: 'resident.uidai.gov.in Step 2: You will be taken to the official page of UIDAI. Step 3: On 'Retrieve EID\/UID' page select what you want to recover - 'Aadhaar Number' or 'Enrolment Number'. Step 4: Enter your personal details such as Name, email id, and phone number. Step 5: Click on 'Send OTP' option. Step 6: You will receive the OTP on the registered mobile number. Step 7: After verifying you will get an option to download your Aadhaar card. What is UIDAI? The Unique Identification Authority of India (UIDAI) is a statutory authority established under the provisions of the Aadhaar (Targeted Delivery of Financial and Other Subsidies, Benefits and Services) Act, 2016 (\u201cAadhaar Act 2016\u201d) on July 12, 2016 by the Government of India, under the Ministry of Electronics and Information Technology (MeitY).