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1 million bytes

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djj55

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Feb 6, 2006
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On the side of a blu-ray disc pack it has:
1 GB = 1000 MB
1 MG = 1 million bytes

For some reason this struck me as wrong. Yes I know these are the approximate values, but seeing the million spelled out my first thought was 1 megabyte.

The other thing is what about the other 48,576 bytes? Even if I had a million dollars 48,576 more is still be important.

Guess I need to get to work and stop over analyzing packaging.

djj
The Lord is my shepherd (Psalm 23) - I need someone to lead me!
 
Assuming that "MG" is a typo and should actually read "MB", then the million is actually correct.
Initially, a kB was a k-Byte, i.e. as "kay" Byte, NOT a "kilo" Byte.

1 MB is actually one "Mega"byte with "Mega" being an SI prefix meaning "million". Hence a Megabyte truly has a million bytes.

What you are thinking of is the original idea behind it which is now called "Mebibyte", abbreviated MiB, which contains 1,048,576 bytes.

Quite a nice cheat this. Now they can sell us 8 GB and leave us with a meagre 7.45 GiB usable space. [poke]

“Knowledge is power. Information is liberating. Education is the premise of progress, in every society, in every family.” (Kofi Annan)
Oppose SOPA, PIPA, ACTA; measures to curb freedom of information under whatever name whatsoever.
 
Yes I made a typo. Did not know about the MiB. But two guy's in black suites just walked in.

As stated, it for some unknown reason struck me as wrong. However, I know it is correct.

djj
The Lord is my shepherd (Psalm 23) - I need someone to lead me!
 
Here at work we (kind of) use MG, which not very many people know what it is.
Until 95 all units here were English, so we had Feet, SqFt, Yards, Gallons, miles, tons, etc. In 95 ‘federales’ said: you better do that in metric or you don’t get no money from us no more. So ‘metric’ system was introduced, and new units are here: meters, sq meters, liters, kilometers, MG

MG stand for Mega Grams, which is a million grams, which is a metric ton

Then a few years later federales said: well, we don’t care no more what you use, do whatever you want.

The mess is still around... :-(

Have fun.

---- Andy
 
Okay, here are the classic definitions:

Decimal Name/Abbrev: kilobyte (kB) ; Dec. Rep.: 10[sup]3[/sup] ; Bin. Equiv.: 2[sup]10[/sup]; IEC Bin. Name/Abbrev.: kibibyte (KiB)
Decimal Name/Abbrev: megabyte (MB) ; Dec. Rep.: 10[sup]6[/sup] ; Bin. Equiv.: 2[sup]20[/sup]; IEC Bin. Name/Abbrev.: mebibyte (MiB)
Decimal Name/Abbrev: gigabyte (GB) ; Dec. Rep.: 10[sup]9[/sup] ; Bin. Equiv.: 2[sup]30[/sup]; IEC Bin. Name/Abbrev.: gibibyte (GiB)
Decimal Name/Abbrev: terabyte (TB) ; Dec. Rep.: 10[sup]12[/sup]; Bin. Equiv.: 2[sup]40[/sup]; IEC Bin. Name/Abbrev.: tebibyte (TiB)
Decimal Name/Abbrev: petabyte (PB) ; Dec. Rep.: 10[sup]15[/sup]; Bin. Equiv.: 2[sup]50[/sup]; IEC Bin. Name/Abbrev.: pebibyte (PiB)
Decimal Name/Abbrev: exabyte (EB) ; Dec. Rep.: 10[sup]18[/sup]; Bin. Equiv.: 2[sup]60[/sup]; IEC Bin. Name/Abbrev.: exbibyte (EiB)
Decimal Name/Abbrev: zettabyte (ZB); Dec. Rep.: 10[sup]21[/sup]; Bin. Equiv.: 2[sup]70[/sup]; IEC Bin. Name/Abbrev.: zebibyte (ZiB)
Decimal Name/Abbrev: yottabyte (YB); Dec. Rep.: 10[sup]24[/sup]; Bin. Equiv.: 2[sup]80[/sup]; IEC Bin. Name/Abbrev.: yobibyte (YiB)

Dec. Rep. = Decimal Representation (but not equivalent to Binary values)
Bin. Equiv. = Binary Equivalent value of Decimal Name and IEC Binary Name
IEC = International Electrotechnical Commission

[santa]Mufasa
(aka Dave of Sandy, Utah, USA)
“People may forget what you say, but they will never forget how you made them feel.
 
There actually is a difference, if you talk about Disc space or RAM. 1MB RAM always was and will be 2^20 Byte, and not just 1 million. The point is, SI prefixes are only standardised for SI Units, and Byte is no SI Unit. The binary prefixes Kibi,Mebi,Gibi, denoting Kilo binary Mega binary Giga binary are a IEC standard andnot SI.

So for that matter you're not totally wrong about thinking of the "binary kilo" of 2^10, you have physicists on your side. RAM has the nature of being addressed by N address lines, and thus powers of 2 play a role, not the decimal system, and therefore it would be right to speak of several GiB of RAM, instead of GB. Now look into your control center.

Disc capacities depend on the area and density of Bits/area, and there is no strong dependancy on powers of two, rather of Pi and the number of discs or platters and of course you can advertise with higher figures. Indeed no RAM vendor advertises with MiB or GiB capacities, although they really could. Nobody would understand them, at least here in Germany or Europe.

And to make the confusion perfect, SSDs, though being Flash RAM are advertised with the SI prefixes factors, as they still count more to the persisted storage memory.

Bye, Olaf.
 
Many moons ago, in a job far, far away, I had a chart on the wall for the metric units for grams and liters. Were M was mega and m was milli.

Note this was pre-PC. After reading Andy's post, I remember having to product two copies of a document one using British units and one using metric units for the Air Force.

djj
The Lord is my shepherd (Psalm 23) - I need someone to lead me!
 
> 1 GB = 1000 MB

Is wrong, since bits and bytes are a base eight numbering system.

1GB = 1024MB

computer studies just isn't the same in school these days [pc2]

ACSS - SME
General Geek



1832163.png
 
which is a metric ton
Actually a metric "ton" is a metric tonne

AND Gas, water and electricity are measured in meters distance is measured in metres :-D

Chris.

Indifference will be the downfall of mankind, but who cares?
Time flies like an arrow, however, fruit flies like a banana.
Webmaster Forum
 

That’s why I try to explain here at my work that using MG (mega grams) is like saying: “My back-yard swimming pool holds 45 000 000 tea-spoons of water”.
:)

Have fun.

---- Andy
 
I had heard that the rounding of MegaByte to 1,000,000 was officially, "rounding for marketing purposes".

In other words, dumbed down for the masses.

 
Not really dumbed down for the masses... storage vendors just like to make it sound like you're getting more bytes for your buck! And the bigger drives get, the more it works in their favour... your brand new 1 Exabyte hard disk will only contain ~909 TiB.

Annihilannic
[small]tgmlify - code syntax highlighting for your tek-tips posts[/small]
 
Whoops... I meant petabyte in my example. :)

Annihilannic
[small]tgmlify - code syntax highlighting for your tek-tips posts[/small]
 
Annihilannic, true.

And what makes this annoying and confuses non tekkies is, typical drive volumes (in this example for SSDs) nowadays are 64GB, 128GB, 256GB, 512GB. So they follow the binary norm of doubling the capacity and make it seemingly the unit also is meaning the binary equivalents, while it means the metric factors.

Wikipedia says the specs are 25,025,314,816 bytes for a single layer 12 inch BD, which is labelled 25GB. This obviously is measuring this in metric units. Same goes for 4,707,319,808 = 4.7 GB of a DVD. No matter what unit you expected, the factor of a BD layer capacity in comparison to a DVD layer cpacity is about 5.3 anyway. It of course disappointing you can only store 23.3 or 4.4 GB respectively on these layers. But as you backup HDD space, you have the same downsizing factor there. You can store a 256 GB HDD on about 10 BDs. Due to compression you most probably only need 5 or less, if the hdd isn't yet full.

I don't know if other locales than germany/europe use the MiB, GiB, TiB etc. nomenclature at all. In germany the unit prefixes have different meanings when applied to RAM or disc space.

Not only words, but also units should mean what they mean and not need the context, but it's not new, this is not the case also with normal words.

Bye, Olaf.
 
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