Mibibyte
The mebibyte is a multiple of the unit byte for digital information. The binary prefix mebi means 220, therefore one mebibyte is equal to 1048576bytes = 1024 kibibytes. The unit symbol for the mebibyte is MiB. Technically a megabyte (MB) is a power of ten, while a mebibyte (MiB) is a power of two, appropriate for binary machines.
The unit was established by the International Electrotechnical Commission (IEC) in 1998. It was designed to replace the megabyte when used in the binary sense to mean 220 bytes, which conflicts 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. Many Linux distributions use the unit, but it is not widely acknowledged within the industry or media.
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 × 1024 bytes, or 1048576bytes.
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 denotes 1000 × 1000 bytes. The discrepancy may cause confusion, since operating systems using the binary method report lower numerical values for storage size than advertised by manufacturers, such as disk drive manufacturers who strictly use decimal units.
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