The Aadhaar Card is a unique identification document distributed by the Government of India. It features a 12-digit unique identification number associated with an individual's biometric and demographic data. This card serves as verified proof of identity and address across India.

To download Aadhaar Card online, individuals can visit the official UIDAI website. The process involves inputting the Aadhaar number along with other necessary details to access and download the e-Aadhaar in PDF. The document is password-protected, making it printable and valid for identification purposes.

One can download the Aadhaar Card using different approaches:

• Using Aadhaar Number: Navigate to the UIDAI site, select "Download Aadhaar," opt for "Aadhaar Number" option, and insert the 12-digit number. After entering a security code, an OTP (One-Time Password) is sent to the registered phone number, which, once input, allows the e-Aadhaar download.
• Using Enrolment Number: Accessible through the same UIDAI portal under the "Download Aadhaar" menu. Select "Enrolment ID," input the 14-digit ID, followed by the security code. The OTP received on your mobile completes the process, enabling the e-Aadhaar download.

The e-Aadhaar card carries equal validity to the physical copy for identity and address proof, useful for opening bank accounts, loan applications, obtaining mobile connections, among other services.

In summary, downloading the Aadhaar Card online is efficient and straightforward, providing a digital version of one’s Aadhaar Card which is legitimate for identity proof usage. It's crucial to maintain the security of the e-Aadhaar by keeping it securely password-protected and safeguarding it against unauthorized access.