Zettabytes is now the largest unit of digital measurement.

It's official. Zettabytes is now the largest unit of digital measurement.

The size of the "digital universe" will swell so rapidly this year that a new unit — the zettabyte — has been invented to measure it. It has overtaken petabytes as the largest unit of digital measurement.

One zettabyte is equal to one million petabytes, or 1,000,000,000,000,000,000,000 individual bytes.

Humanity's total digital output currently stands at 8,000,000 petabytes — each of which represent a million gigabytes — but is expected to pass 1.2 zettabytes this year, London's Daily Telegraph has reported.

In fact, the current size of the world's digital content is equivalent to all data that could be stored on 75 billion Apple iPads, or the amount that would be generated by everyone.
How much information is out there?
For most of us, "a crapload" is a sufficiently accurate answer. But for a few obsessive data analysts, more precision is necessary. According to a recent study by market-research company IDC, and sponsored by storage company EMC, the size of the information universe is currently 800,000 petabytes. Each petabyte is a million gigabytes, or the equivalent of 1,000 one-terabyte hard drives.
If you stored all of this data on DVDs, the study's authors say, the stack would reach from the Earth to the moon and back.
That's a 62% increase over the amount of digital information floating around the year before — but it's just a down payment on next year's total, which will reach 1.2 million petabytes, or 1.2 zettabytes.
If these growth rates continue, by 2020 the digital universe will total 35 zettabytes, or 44 times more than in 2009.
It's interesting to compare IDC's study with a recent UC San Diego report on how much information Americans consume per year. According to that study, media consumption in 2008 added up to 3.6 zettabytes and 10,845 trillion words, or about 34 gigabytes per person per day.
Much of the media we view (TV shows, streaming video from YouTube) is centrally stored, on internet-connected servers, so the totals for consumption are naturally higher than the storage requirements.
IDC notes that while data storage will increase 44-fold by 2020, the number of IT professionals worldwide will only grow by 40%, which means each IT guy is going to have a lot more data to oversee.