Except it's not because it's constantly ambiguous in computing.
E.g. Macs measure file sizes in powers of 10 and call them KB, MB, GB. Windows measures file sizes in powers of 2 and calls them KB, MB, GB instead of KiB, MiB, GiB. Advertised hard drives come in powers of 10. Advertised memory chips come in powers of 2.
When you've got a large amount of data or are allocating an amount of space, are you measuring its size in memory or on disk? On a Mac or on Windows?
And that is because some people didn't like that a kilobyte was 1024 bytes instead of 1000, so they started using 1000 instead, and then that created confusion, so then they made up new term "kibibyte" that used 1024, and now it's all a mess.
And in most cases, using 1024 is more convenient because the sizes of page sizes, disk sectors, etc. are powers of 2.
> Macs measure file sizes in powers of 10 and call them KB, MB, GB.
That doesn't conform to SI. It should be written as kB mB gB. Ambiguity will only arise when speaking.
> Advertised hard drives come in powers of 10.
Mass storage (kB) has its own context at this point, distinct from networking (kb/s) and general computing (KB).
> When you've got a large amount of data or are allocating an amount of space, ...
You aren't speaking but are rather working in writing. kb, kB, Kb, and KB refer to four different unit bit counts and there is absolutely zero ambiguity. The only question that might arise (depending on who you ask) is how to properly verbalize them.
Oh. Indeed you're correct. I was thinking in computer terms instead of scientific terms. Personally I see this as reinforcing that computers as a context wouldn't really benefit from using "proper" SI.
Note that no one is going to confuse mB for millibytes because what would that even mean? But also in practice MB versus Mb aren't ambiguous because except for mass storage no one mixes bytes with powers of ten AFAIK.
And let's take a minute to appreciate the inconsistency of (SI) km vs Mm. KB to GB is more consistent.
> no one is going to confuse mB for millibytes because what would that even mean?
Data compression. For example, look at http://prize.hutter1.net/ , heading "Contestants and Winners for enwik8". On 23.May'09, Alex's program achieved 1.278 bits per character. On 4.Nov'17, Alex achieved 1.225 bits per character. That is an improvement of 0.053 b/char, or 53 millibits per character. Similarly, we can talk about how many millibits per pixel JPEG-XL is better than classic JPEG for the same perceptual visual quality. (I'm using bits as the example, but you can use bytes and reach the same conclusion.)
Just because you don't see a use for mB doesn't mean it's open for use as a synonym of MB. Lowercase m means milli-, as already demonstrated in countless frequently used units - millilitre, millimetre, milliwatt, milliampere, and so on.
In case you're wondering, mHz is not a theoretical concept either. If you're generating a tone at say 440 Hz, you can talk about the frequency stability in millihertz of deviation.
E.g. Macs measure file sizes in powers of 10 and call them KB, MB, GB. Windows measures file sizes in powers of 2 and calls them KB, MB, GB instead of KiB, MiB, GiB. Advertised hard drives come in powers of 10. Advertised memory chips come in powers of 2.
When you've got a large amount of data or are allocating an amount of space, are you measuring its size in memory or on disk? On a Mac or on Windows?