K3b sees 4.7GB DVD+R as 4.4 GB

Jeff Vian jvian10 at charter.net
Sun Jan 15 06:14:14 UTC 2006


On Sun, 2006-01-15 at 12:37 +1030, Tim wrote:
> On Sat, 2006-01-14 at 07:41 -0600, Jeff Vian wrote:
> > As has already been said by Peter, this is a marketing speak.
> 
> No, not really.  It all stems from the ABSOLUTe MISUSE of kilo by the
> computer fraternity.  Kilo means, and ONLY means, "one times ten to the
> third power", i.e. "one thousand".  Likewise, Mega means, and ONLY
> means, "one times ten to the sixth power", i.e. "one million".  Even if
> you change base units (so you're not using powers of ten) to express the
> worth of Kilo and Mega, etc., they've still got to mean one thousand or
> one million, etc., not some *slightly* different value.
> 
Kilo and Mega do mean 10^3 and 10^6 when using human terms (the decimal
system).
In the binary system Kilo means 1024 (2^10) and Mega means 1048576 (2^20
or 1024 * 1024).

This is far from misuse, simply a different mathematical numbering
system.

> For an incredibly stupid reason, the computer fraternity took SI units
> with fixed meanings and abused them for their own purposes instead of
> using them as they're supposed to be used and/or creating their own
> abreviation for 1024 bits.  That has finally been rectified with KiB and
> MiB, but the adoption of it is far from widespread.  But the damage
> caused by this stupidity is widespread, and probably never going to be
> completely overcome.  People still won't use KiB and MiB, and they still
> keep abusing KB to mean 1024, and some others will still use it properly
> as 1000 (decimal).
> 

A byte is 8 bits, or 2^8 == 256 in decimal
KiloBytes means 2^10 == 1024 bytes == 1024*8 (8192) bits
(I had to throw in that even more misunderstood fact. :)  )
MegaBytes means 2^20 == 1048576 bytes
similarly for GigaBytes, TeraBytes, etc

This is far from stupid, since computers do all calculations in powers
of 2 (binary), and converting from binary to decimal is only needed when
one party (the human) needs to easily understand the value.

The separation comes from the environment.  In math and non-computer
terms it is powers of 10. (Humans are used to the decimal system)
In computer terms it is powers of 2. (the binary system)

> There's only one mob to blame for the confusion of what KB and MB, etc.,
> mean:  The computer programmers.
> 
> And it doesn't stop there, either.  Is one MB 1024 KB, or something
                                      ^^^^^^^^^^^^^^^^^   YES         
> else?  People have different opinions about that, so it makes MB even
> more vague than KB.  What about Giga and Terra, are they each 1024 times
> their inferior?
YES, as long as we are talking binary terms and not decimal.
> 
> Opinions about thing that need to be facts should have been properly
> sorted out many years ago.  Opinions are useless in computer programming
> where one thing has to work with another.  I've already seen this thing
> screw up drive handling on another personal computer OS, where drives
> could get filled to 101% capacity (and error, of course), because
> different programmers working on it had different idea about what Kilo
> and Mega meant.
> 
That was an error in the concept used by the programmer (or was that a
misunderstanding on the part of the observer.).
It is clearly defined that in computer terms (binary) kilo is 1024, and
in decimal terms kilo is 1000.

The errors occur when those using them do not keep the terms related to
the environment where they are used.

> There's only three ways to be understood:
> 
> Use properly defined terms (KiB, MiB, etc.).
> Use bytes with no multipliers.
> Use bits with no multipliers.
> 
Bytes and bits are often misused as well.
What is the actual rated speed of a 56k leased line?  Is it 56kb
(kilobits) or 56kB (kilobytes).
In fact it is usually a 56kb line, but it is easy to misinterpret even
that.

> But don't EVER use KB, MB, GB, TB, etc., if you want precision.
> 
The quality of communication is in the way the data is presented, and
careless notation and (sometimes deliberate) misuse of terms cause us
all many problems.

The start of this was a dig at a common 'deliberate' misuse of terms to
enhance advertising. Selling a 4.7gB DVD disk as holding 4.7gB of data.
The raw size may be 4.7GB, but the usable size is somewhat less.  Or
selling a 200GB hard drive that us usable only as about 194GB. (The
disclaimer in the fine print tells how that is calculated.)  That is
also similar to selling an 80 min 700MB CD. It actually holds almost
800MB of data, but due to filesystem overhead and formatting the data
_content_ is only 700 MB. the remaining 100MB is lost to overhead.
(However, you actually can put 800MB of music in audio format on one --
no filesystem overhead there.)

> -- 
> Don't send private replies to my address, the mailbox is ignored.
> I read messages from the public lists.
> 




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