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The mebibyte is a multiple of the unit byte for digital information. The binary prefix ''mebi'' means 220, therefore one ''mebibyte'' is equal to . The unit symbol for the mebibyte is MiB. The unit was established by the International Electrotechnical Commission (IEC) in 1998.〔International Electrotechnical Commission (January 1999), IEC 60027-2 ''Amendment 2: Letter symbols to be used in electrical technology - Part 2: Telecommunications and electronics''.()〕 It was designed to replace the megabyte, which is still being used in many contexts to represent 220 bytes, which is incompatible with the definition of the prefix mega in the International System of Units (SI) as a multiplier of 106. The binary prefixes have been accepted by all major standards organizations and are part of the International System of Quantities.〔(【引用サイトリンク】url=http://www.iso.org/iso/catalogue_detail?csnumber=31898 )〕 Many Linux distributions use the unit, but it is not yet widely published within the industry or media.〔''Upgrading and Repairing PCs'', Scott Mueller, Pg. 596, ISBN 0-7897-2974-1〕〔''The silicon web: physics for the Internet age'', Michael G. Raymer, Pg. 40, ISBN 978-1-4398-0311-0〕〔(Knuth: Recent News ). Cs-staff.stanford.edu. Retrieved on 2011-01-07.〕〔Atwood, Jeff. (2007-09-10) (Gigabyte: Decimal vs. Binary ). Coding Horror. Retrieved on 2011-01-07.〕 ==Definition== : 1 MiB = 220 bytes = 1024 kibibytes = The prefix ''mebi'' is a binary prefix derived from the words mega and binary, indicating its origin in the closeness in value to the SI prefix ''mega''. One mebibyte (MiB) is 220, i.e. 1024 x 1024 bytes, or . Despite its official status, the unit ''mebibyte'' is not commonly used even when reporting byte counts calculated in binary multiples, but is often represented as megabytes. Formally, one megabyte means 1000 x 1000 bytes. Disk drive manufacturers strictly use decimal units, and the megabyte means . The discrepancy may cause confusion, since operating systems using the binary method report lower numerical values for storage size than advertised by manufacturers. Many operating systems compute file size in mebibytes, but report the number as MB. For example, all versions of the Microsoft Windows operating system show a file of 220 bytes as "1.00 MB" or "1,024 KB" in its file properties dialog and show a file of 106 () bytes as 976 KB. All versions of Apple's operating systems had the same behavior until Mac OS X version 10.6, which instead uses megabytes for all file and disk sizes, so it reports a 106 byte file as 1 MB. The Ubuntu developer Canonical implemented an updated units policy in 2010 and as of Ubuntu 10.10 all versions now adhere to the IEC binary prefix for base-2 units and the SI prefix for base-10 units. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Mebibyte」の詳細全文を読む スポンサード リンク
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