OpenEuphoria

Re: Bytes Question

• Posted by Derek Parnell <ddparnell at bigpond.com> Jul 07, 2006
• 701 views

This link is informative.

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

Summary:
Because of inconsistencies in the use of SI-derived prefixes such as kilo- and
mega-, the exact number can be any one of the following:

1,048,576 bytes (1,0242, 220): This definition is used for nearly all
discussions of computer memory (as computer addresses are naturally powers of
two, making it efficient to manufacture memory in power-of-two capacities) and
file storage. As of 2005, most software uses this definition to express storage
capacity (e.g. file size).

1,000,000 bytes (1,0002, 106): This is the definition recommended by SI and IEC.
It is used primarily in networking contexts and most storage media, particularly
hard drives and DVDs. This definition of 'mega-' as a SI prefix is consistent
with the other SI prefixes, and with many other uses of the prefix in computing,
such as CPU clock speeds or measures of performance.

1,024,000 bytes (1,024×1,000): This definition occurs rarely. It was used in a
small number of storage contexts, most notably the "1.44 MB" (actually 1,474,560
bytes), and the "3.5-inch" (actually 90 mm) high-density floppy diskette.

Several attempts to resolve these inconsistencies have been proposed, most
notably the standard created by the IEC to redefine 1,048,576 bytes as a
"mebibyte". This standard has been adopted by several organizations, such as the
NIST and IEEE.


-- 
Derek Parnell
Melbourne, Australia
Skype name: derek.j.parnell