Try this one:
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What is zettabyte? - Definition from WhatIs.com
A zettabyte is a measure of storage capacity and is 2 to the 70th power bytes or, in decimal, approximately a thousand exabytes or a million terabytes.
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searchstorage.techtarget.com/definition/zetta
A zettabyte is a measure of storage capacity and is 2 to the 70th power bytes or, in decimal, approximately a thousand exabytes or a million terabytes. So, a zettabyte is equivalent to a kilo-exabyte or a mega-terabyte, assuming such terminology was in widespread use. It's not, but it makes sense to me :).