quantifiers In techspeak and jargon, the standard metric prefixes used in the SI
(Système International) conventions for scientific measurement have
dual uses. With units of time or things that come in powers of 10, such as
money, they retain their usual meanings of multiplication by powers of
Here are the SI magnifying prefixes, along with the corresponding binary interpretations in common use: prefix decimal binary kilo- 1000^1 1024^1 = 2^10 = 1,024 mega- 1000^2 1024^2 = 2^20 = 1,048,576 giga- 1000^3 1024^3 = 2^30 = 1,073,741,824 tera- 1000^4 1024^4 = 2^40 = 1,099,511,627,776 peta- 1000^5 1024^5 = 2^50 = 1,125,899,906,842,624 exa- 1000^6 1024^6 = 2^60 = 1,152,921,504,606,846,976 zetta- 1000^7 1024^7 = 2^70 = 1,180,591,620,717,411,303,424 yotta- 1000^8 1024^8 = 2^80 = 1,208,925,819,614,629,174,706,176 Here are the SI fractional prefixes: prefix decimal jargon usage milli- 1000^-1 (seldom used in jargon) micro- 1000^-2 small or human-scale (see The prefixes zetta-, yotta-, zepto-, and yocto- have been included in
these tables purely for completeness and giggle value; they were adopted in
1990 by the There are, of course, some standard unit prefixes for powers of 10. In the following table, the ‘prefix’ column is the international standard prefix for the appropriate power of ten; the ‘binary’ column lists jargon abbreviations and words for the corresponding power of 2. The B-suffixed forms are commonly used for byte quantities; the words ‘meg’ and ‘gig’ are nouns that may (but do not always) pluralize with ‘s’. prefix decimal binary pronunciation} kilo- k K, KB, Confusingly, hackers often use K or M as though they were suffix or numeric multipliers rather than a prefix; thus “2K dollars”, “2M of disk space”. This is also true (though less commonly) of G. Note that the formal SI metric prefix for 1000 is ‘k’; some use this strictly, reserving ‘K’ for multiplication by 1024 (KB is thus ‘kilobytes’). K, M, and G used alone refer to quantities of bytes; thus, 64G is 64 gigabytes and ‘a K’ is a kilobyte (compare mainstream use of ‘a G’ as short for ‘a grand’, that is, $1000). Whether one pronounces ‘gig’ with hard or soft ‘g’ depends on what one thinks the proper pronunciation of ‘giga-’ is. Confusing 1000 and 1024 (or other powers of 2 and 10 close in
magnitude) — for example, describing a memory in units of 500K or
524K instead of 512K — is a sure sign of the
We observe that this would leave the prefixes zeppo-, gummo-, and chico- available for future expansion. Sadly, there is little immediate prospect that Mr. Burke's eminently sensible proposal will be ratified.] |