Exabyte
From Free net encyclopedia
- For the company that manufactures data backup products, see Exabyte Corporation.
An exabyte (derived from the SI prefix exa-, and abbreviated as EB) is a unit of information or computer storage equal to approximately one quintillion bytes.
Because of irregularities in the definition and usage of terms for byte multiples, the exact number can be either one of the following:
- 1,000,000,000,000,000,000 bytes — 10006, or 1018.
- 1,152,921,504,606,846,976 bytes — 10246, or 260.
Because of these irregularities, the term "exbibyte" has been proposed as an unambiguous reference to the latter value. (See binary prefixes.)
As of 2005, exabytes of data are almost never encountered in any practical context. For example, the total amount of printed material in the world is estimated to be around five exabytes. However, one may hear of 16 or 18 exabytes of address space when discussing 64-bit architectures.
It was estimated that by the end of 1999, the sum of human knowledge (including audio, video and text) was 12 exabytes. [1]
Research at the UC Berkeley School of Information suggests that 5 exabytes of new information was created in 2002 alone, 92% of it on magnetic media, mostly on hard discs. [2]