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On Sun, Mar 30, 2014 at 7:44 PM, Douglas James Dunn |
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<djdunn.safety@×××××.com> wrote: |
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> The system you are most familiar with really depends on what Operating |
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> System you use. if you don't use computers you probably were exposed to |
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> either the SI units or imperial base 10 units. |
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|
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SI units ARE in base 10. Most imperial units aren't in base 10, and |
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the SI prefixes aren't generally used with imperial units. You don't |
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usually report height in centiyards, etc. |
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|
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There seems to be some kind of misconception that this has something |
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to do with imperial vs metric units. |
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|
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Bits and bytes are such a modern concept that they were pseudo-metric |
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from the start, but programmers tended to use the SI prefixes in |
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non-SI ways - defining a kilobyte as 1024 bytes. "Kilo" is an SI |
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prefix, but the SI defines it as 1000, not 1024. |
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|
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The 1024-byte kilobyte was never metric or SI or imperial. Fairly |
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recently JEDEC codified the 1024-byte kilobyte, but also endorsed the |
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1024-byte kibibyte, and the usage obviously predates that standard. |
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Before then, programmers never really had a "standard" for the |
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kilobyte. Since programmers don't tend to do a lot of compound units, |
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getting their terms endorsed by a standards body was probably not much |
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of a priority. If they had gone to the SI/ISO (or whatever was around |
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in the 60s) they'd almost certainly have been shot down on having a |
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1024-byte kilobyte. |
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|
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Rich |