The Social Security Number has its origins in the years of the Great Depression. During this period of economic recession in the US, the Roosevelt government launched the “New Deal”, a series of programmes to provide relief and employment to the poor.

In 1936, under the Social Security Act, it began using a nine-digit number, the Social Security Number, to track the earnings of workers and compute the amount of social security benefits to be credited to their accounts.

Over the years, the ease of using the number led more government agencies to incorporate it in their records. In 1961, for instance, the Internal Revenue Service began using the Social Security Number for taxpayer identification, similar to the Permanent Account Number in India.

With no legal restrictions on use of the Social Security Number by private companies, several businesses such as credit bureaus started asking individuals for their Social Security Number and storing it.

But in 1977, the Carter administration clarified that while it may used to be verify whether an individual had the legal permit to work, the Social Security Number could not serve as an identification document.

The Social Security Administration website states in a 2009 bulletin: “The card was never intended to serve as a personal identification document – that is, it does not establish that the person presenting the card is actually the person whose name and SSN appear on the card.”

By contrast, Aadhaar has been designed as a single, universal, digital identity number that any registered entity, whether public or private, can use to “authenticate” an Indian resident. Anyone who has lived in India for 182 days can enroll in Aadhaar for proof of identity, while only citizens and those authorised to work in the US can obtain a Social Security Number.