Exabyte
| Multiples of bytes | ||||||
|---|---|---|---|---|---|---|
| Decimal prefixes | Binary prefixes | |||||
| Name | Symbol | Multiple | Name | Symbol | Multiple | |
| kilobyte | kB | 103 | kibibyte | KiB | 210 | |
| megabyte | MB | 106 | mebibyte | MiB | 220 | |
| gigabyte | GB | 109 | gibibyte | GiB | 230 | |
| terabyte | TB | 1012 | tebibyte | TiB | 240 | |
| petabyte | PB | 1015 | pebibyte | PiB | 250 | |
| exabyte | EB | 1018 | exbibyte | EiB | 260 | |
| zettabyte | ZB | 1021 | ||||
| yottabyte | YB | 1024 | ||||
An exabyte (derived from the SI prefix exa-) is a unit of information or computer storage equal to one quintillion (one long scale trillion) bytes. It is commonly abbreviated EB.
Because of irregularities in using the binary prefix in the definition and usage of the kilobyte, the exact number in common practice could 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. This capacity may be expressed unambiguously as an exbibyte.
As of 2005, exabytes of data are almost never encountered in a 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 exabytes (exbibytes) of address space when discussing 64-bit architectures.
Exabyte is also the name of a company that manufacturers computer data backup products. Exabyte Corporation is based in Boulder, Colorado.
As of February 2005, no one has made a tape capable of holding a full exabyte.