From the article titled “Lunch with Hal” in issue #1 of Think Quarterly
In 2010, the human race created 800 exabytes of information, from tweets and Facebook updates to PowerPoint presentations and photographs. That’s 800 billion gigabytes, or the amount of data you can fit on 75 billion 16-gig iPads. To put that into context, between the dawn of civilisation and 2003, we only created five exabytes; now we’re creating that amount every two days. By 2020, that figure is predicted to sit at 53 zettabytes (53 trillion gigabytes) – an increase of 50 times.