Stop abusing SI prefixes!
Cause 1024 just ain't 1000.
Hi there!
Welcome to this little webpage, devoted to the noble goal of trying to stop the abusing and massacration of SI prefixes, which has sadly become a somewhat too popular practice.
It seems a fancy website on a dedicated domain is a fairly effective way of getting a point across (because who reads those boring standards and RFC's anyway?), so I'll try that.. (okay, not fancy yet. pretty theme welcome).
If you notice anything wrong on this page or if you have suggestions, you can let me know.
So, what's the problem?
See this?
They are called SI prefixes. A shorthand to prefix a unit, which makes it easier and clearer to deal with a broad range of quantities of that unit. Pretty clever stuff (once you manage to wrap your head around their immense complexity). Based on a decimal system, because that's how we count.
On the 11th CGPM conference, held by BIPM (the same guys who invented things like the gram and the metre - Yes I know the US has not adopted the metric system but that's a different story, read on), they were standardized.
That was way back in 1960.
1960.
That's 4 years before the 'BASIC' language came to life, and 9 years before the introduction of ARPANET (you know, that little network that grew to become the internet as we know it today. It didn't have e-mail)
You remember that, 1960? Neither do I. Maybe because we both weren't even born back then. But I learned about SI prefixes in 3rd grade (or whatever) science classes.
Even if you live in one of the three "special" countries which haven't adopted the totally awesome metric system there is no excuse:
Both the IEC (which includes the USA) and the US National Instute of Standards and Technology support SI prefixes)
Apparently some of the early computer engineers (well, if you think they were worthy of the term "engineer") were sloppy and thought it was OK to ignore some of the basic principles of science/math:
In computing, you deal with a lot of binary numbers (base 2, rather then base 10). Since those numbers also can get large, some prefixes for the binary system were/are of course desired.
Instead of actually defining such prefixes correctly like any sane human being would do, they had the bright idea of using the same names of prefixes which already existed, but give them other meanings. (what could possibly go wrong?)
Since 2^10 (1024) is the closest power of two to 10^3 (=1000, =k), they started using k as such. Similar abuses happened for M, and later on G and T.
And due to some kind of mass-confusion/conformist behavior/whatever, we're stuck with that shit for decades now. (the JEDEC "standardization" association didn't help either. I wouldn't exactly call formalizing incorrect usage "standardisation")
So while all other sciences are happily doing their thing, solving interesting problems and helping the progress of mankind, we computer scientists/engineers are looking like complete retards. Time to get our shit together.
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Solution
There is really no need we should spend this much of our time fixing "1000 ≠1024 bugs", clarifying what we mean to each other, trying to interpret ambigious information or explaining mom/dad/uncle why their hard disk is not smaller then it's advertised to be (or worse: a lot of people actually believe that crap and spread the myth around. read on..)
Guess what, there actually is a standard that adresses this issue, a standard which dictates which prefixes you should use to represent powers of two. A standard 12 years old.
Again, our American friends are covered as well
Common myths
- Hard disk vendors lie
Wrong. They just honor SI. As should you. Stop falsely accusing honest folks. Get informed.
Oh yeah, and also don't blame them for the fact that your file system and MBR need space to store their stuff.
- I don't need to be so pedantic, people will get what I'm talking about.
Seriously? I mean... really?
- Ubuntu is lame.
Maybe, but at least they have a sensible units policy. Debian is trying to fix it aswell. Even O'Reilly (almost) gets it!. I'm told MacOS UI's are doing the right thing, and some Redmond-based operating system is of course doing it completely wrong again.
While we're at it
- 'k' is not the same as 'K'
- The hertz unit of frequency: 'Hz'. Not 'hz' or 'HZ'
- Get your ******* units right: 'B' means byte, 'b' means bit. (IEEE 1541)
- A prefix without a unit is meaningless: use kB, MiB, or whatever. But not k or M. (I'm looking at you GNU coreutils!)
In Conclusion
Study this:
| SI (base 10, decimal) prefixes | IEC (base 2, binary) prefixes |
|---|
| value | shorthand | value | shorthand |
| 10^3 = 1000 | k (kilo) | 2^10 = 1024 | Ki (kibi) |
| 10^6 = 1000^2 | M (mega) | 2^20 = 1024^2 | Mi (mebi) |
| 10^9 = 1000^3 | G (giga) | 2^30 = 1024^3 | Gi (gibi) |
| 10^12 = 1000^4 | T (tera) | 2^40 = 1024^4 | Ti (tebi) |
b = bit
B = byte (8 bits)
Got it?
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Prof. M. Kuhne, director of BIPM.
Awesommest guy on the planet
Don't abuse his work |
Sad panda. This is what happens if you molest SI prefixes |
Sources
I wrote this page based on what I found on various sources, but mostly Wikipedia pages.
There should be no factual mistakes (only some subtle exaggerations), so let me know if you found any.
If you want to build a nice layout, get in touch first
