Joe,

I just read your page at
   http://www.inwap.com/tivo/disk-sizes.txt
and I noticed your statement: using binary "giga". There is no binary giga 
since giga is an SI prefix having a fixed meaning of 10^9.

I suggest that you instead use the prefix intended for the meaning of 1024^3, 
namely "gibi" (Gi). Also of use to you on that page will be kibi (Ki), mebi 
(Mi), and tebi (Ti).

For example, on your last line, a terabyte disk will have a capacity of about 
976 762 584 KiB, 953 869.7 MiB, 931 513 GiB, or 0.910 TiB. (You may notice also 
that I use spaces instead of commas to separate groups of 3 digits.)

You can see IEEE Std 1541 (an American National Standard) on this topic. Or, 
you could just google "gibi"; plenty of computer magazines and websites address 
the topic. IEC has a parallel standard saying essentially the same thing, by 
the way.

These prefixes are provided so that one does not have to provide clarification 
to the reader that the prefixes used in a document are not properly used; 
rather one can use the proper prefix and be done with it.

Both "giga" and "gibi" have fixed meanings. They are not user-defineable and we 
are trying to wean computer folks from previous practices of misuse.

I hope that this has been useful for you in updating your page. Thank you for 
your time.

regards,
James R. Frysinger (Jim)



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