yottabyte

n. (Computers) unit of data size equal to 2 to the 80th power bytes or 1024 zettabytes (largest unit of data size)

A yottabyte (derived from the SI prefix yotta-) is a unit of information or computer storage equal to one septillion (one long scale quadrillion or 1024) bytes. It is commonly abbreviated YB. As of 2007, no computer has achieved one yottabyte of storage. In fact, the combined space of all the computers in the world does not amount to one yottabyte. According to one study, the world stored approximately 160 exabytes in 2006, with nearly 1,000 exabytes projected by 2010. When used with byte multiples, the SI prefix may indicate a power of either 1,000 or 1,024, so the exact number may be either:1 septillion, or 1,000,000,000,000,000,000,000,000 bytes — 10008, or 1024, or1,208,925,819,614,629,174,706,176 bytes — 10248, or 280.
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n. yottabyte (Computers), unit of data size equal to 2 to the 80th power bytes or 1024 zettabytes (largest unit of data size)

<unit> 2^80 = 1,208,925,819,614,629,174,706,176 bytes = 1024 zettabytes.
See prefix.
(1997-05-02)