What is MiB Mean in PHPMyAdmin?

Question

When we want to import sql query file. we will see max file limit size, and the unit is MiB.

1. What is MiB mean?
2. why not says MB (MegaByte)?

for more explanation what i mean, i upload the screenshot: http://img683.imageshack.us/img683/4131/phpmyadmins.png

Many Thanks, GusDe

Answer 1

http://en.wikipedia.org/wiki/MiB

The mebibyte is a multiple of the unit byte for digital information. The binary prefix mebi means 220, therefore 1 mebibyte is 1048576bytes. The unit symbol for the mebibyte is MiB.[1] The unit was established by the International Electrotechnical Commission (IEC) in 2000 and has been accepted for use by all major standards organizations. It was designed to replace the megabyte used in some computer science contexts to mean 220 bytes, which is similar to but conflicts with the SI definition of the prefix mega (106).

In short, it's 1M = 1000K vs. 1M = 1024K.

Answer 2

1. One MiB (mebibyte) is 1048576 (1024^2) bytes.
2. Because some people are snobby about the meanings of SI prefixes (powers of 1000) and don't like it when people use them for powers of 1024

Answer 3

The people in charge of such things [edit: in this case, the IEC] got bothered about the fact that a 'kilobyte' (normally) signifies 1024 bytes instead of 1000 bytes. To eliminate any possible confusion they invented a new set of prefixes for digital "stuff" (kibi, mebi, etc.) and picked 'Ki', "Mi", etc., as the abbreviations for them.

Answer 4

It means mebibyte.

1 mebibyte is 1,048,576 bytes

Answer 5

MiB is a mebibyte (I still can't use that word without chuckling), equivalent to 2²⁰ bytes.

The reason it was invented was because mega is an official SI prefix meaning one million. It is not equivalent to 2²⁰.

Having said that, the IT industry (for better or worse) has co-opted those terms to mean the nearest power of two, and anyone caught using childish words like mebibyte and kibibyte is likely to be considered a blithering idiot, and locked away for a long time.

Other than hard-disk manufacturers who found it a neat trick to make it look like their disks are bigger than they actually are, the vast majority of tech-heads I know use the SI prefixes in the non-SI context.