K3b sees 4.7GB DVD+R as 4.4 GB

Kenny Gow kgfedora at swbell.net
Tue Jan 17 08:24:41 UTC 2006


Mike McCarty wrote:
> 
> Please, allow each group its own jargon.
> 
> Mike
Well, I guess you just don't get it. Some of us are members of many
different groups. Let me put it in historical context for you:

from http://physics.nist.gov/cuu/Units/binary.html

Historical context*

Once upon a time, computer professionals noticed that 210 was very 
nearly equal to 1000 and started using the SI prefix "kilo" to mean 
1024. That worked well enough for a decade or two because everybody 
who talked kilobytes knew that the term implied 1024 bytes. But, 
almost overnight a much more numerous "everybody" bought computers, 
and the trade computer professionals needed to talk to physicists and 
engineers and even to ordinary people, most of whom know that a 
kilometer is 1000 meters and a kilogram is 1000 grams.

Then data storage for gigabytes, and even terabytes, became practical, 
and the storage devices were not constructed on binary trees, which 
meant that, for many practical purposes, binary arithmetic was less 
convenient than decimal arithmetic. The result is that today 
"everybody" does not "know" what a megabyte is. When discussing 
computer memory, most manufacturers use megabyte to mean 220 = 1 048 
576 bytes, but the manufacturers of computer storage devices usually 
use the term to mean 1 000 000 bytes. Some designers of local area 
networks have used megabit per second to mean 1 048 576 bit/s, but all 
telecommunications engineers use it to mean 106 bit/s. And if two 
definitions of the megabyte are not enough, a third megabyte of 1 024 
000 bytes is the megabyte used to format the familiar 90 mm (3 1/2 
inch), "1.44 MB" diskette. The confusion is real, as is the potential 
for incompatibility in standards and in implemented systems.

Faced with this reality, the IEEE Standards Board decided that IEEE 
standards will use the conventional, internationally adopted, 
definitions of the SI prefixes. Mega will mean 1 000 000, except that 
the base-two definition may be used (if such usage is explicitly 
pointed out on a case-by-case basis) until such time that prefixes for 
binary multiples are adopted by an appropriate standards body.




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