mebitibytes

A mebibyte is a unit of digital information storage. It is one of the multiples of the unit byte, where the prefix mebi is derived from the binary system. Specifically, a mebibyte is equal to 2^20 bytes, which is equivalent to 1,048,576 bytes. This is distinct from a megabyte, which is a metric unit and is equal to 10^6 bytes, or 1,000,000 bytes. The distinction between binary prefixes like mebi and metric prefixes like mega is important in computing to avoid ambiguity.

The mebibyte is commonly used in contexts where precise binary multiples are relevant, such as in the specification of computer memory (RAM) or file sizes reported by operating systems. For instance, a RAM module might be described as having a capacity of 8 GiB (gibibytes), which would be 8 x 2^30 bytes. Similarly, a file might be reported by an operating system as having a size of 5 MiB (mebibytes), indicating 5 x 2^20 bytes.

The International Electrotechnical Commission (IEC) introduced the mebi prefix and others like kibi, gibi, and tebi in 1998 to standardize binary multiples. Before the introduction of these prefixes, megabyte was often used to refer to both 10^6 bytes and 2^20 bytes, leading to confusion. The use of mebibyte clarifies that the quantity being discussed is based on powers of two. While the IEC prefixes are the standard, the term "megabyte" is still frequently used colloquially and sometimes in industry to refer to binary multiples, particularly in marketing materials for storage devices.