How Much Information Is There in the World?

A study appearing on Feb. 10 in Science Express, an electronic journal that provides select Science articles ahead of print, calculates the world's total technological capacity -- how much information humankind is able to store, communicate and compute.

"We live in a world where economies, political freedom and cultural growth increasingly depend on our technological capabilities," said lead author Martin Hilbert of the USC Annenberg School for Communication & Journalism. "This is the first time-series study to quantify humankind's ability to handle information."

So how much information is there in the world? How much has it grown?

Prepare for some big numbers:

• Looking at both digital memory and analog devices, the researchers calculate that humankind is able to store at least 295 exabytes of information. (Yes, that's a number with 20 zeroes in it.)
• 2002 could be considered the beginning of the digital age, the first year worldwide digital storage capacity overtook total analog capacity. As of 2007, almost 94 percent of our memory is in digital form.

Here is the report The World's Technological Capacity to Store, Communicate, and Compute Information, by Martin Hilbert and Priscila López, Science Magazine, Feb 10, 2011.