1. <unit> The standard metric prefixes used in the {Systeme International d'Units} (SI) conventions for scientific measurement. Here are the SI magnifying prefixes, along with the corresponding binary interpretations in common use: prefix abr decimal binary yocto- 1000^-8 zepto- 1000^-7 atto- 1000^-6 femto- f 1000^-5 pico- p 1000^-4 nano- n 1000^-3 micro- * 1000^-2 * Abbreviation: Greek mu milli- m 1000^-1 kilo- k 1000^1 1024^1 = 2^10 = 1,024 mega- M 1000^2 1024^2 = 2^20 = 1,048,576 giga- G 1000^3 1024^3 = 2^30 = 1,073,741,824 tera- T 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 "Femto" and "atto" derive not from Greek but from Danish. The abbreviated forms of these prefixes are common in electronics and physics. When used with bytes of storage, these prefixes usually denote multiplication by powers of 1024 = 2^10 (K, M, and G are common in computing). Thus "MB" stands for megabytes (2^20 bytes). This common practice goes against the edicts of the BIPM who deprecate the use of these prefixes for powers of two. The formal SI prefix for 1000 is lower case "k"; some, including this dictionary, use this strictly, reserving upper case "K" for multiplication by 1024 (KB is thus "kilobytes"). Also, in data transfer rates the prefixes stand for powers of ten so, for example, 28.8 kb/s means 28,800 bits per second. The unit is often dropped so one may talk of "a 40K salary" (40000 dollars) or "2 meg of disk space" (2*2^20 bytes). The accepted pronunciation of the initial G of "giga-" is hard, /gi'ga/. 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 marketroid. For example, 3.5" microfloppies are often described as storing "1.44 MB". In fact, this is completely specious. The correct size is 1440 KB = 1440 * 1024 = 1474560 bytes. Alas, this point is probably lost on the world forever. In 1993, hacker Morgan Burke proposed, to general approval on Usenet, the following additional prefixes: groucho (10^-30), harpo (10^-27), harpi (10^27), grouchi (10^30). 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. 2. <language> Related to the prefix notation. (2003-05-06)

(prefixes)

A prefix is an affix which is placed before the stem of a word. Adding it to the beginning of one word changes it into another word.

Numeral or number prefixes are prefixes derived from numerals or occasionally other numbers. In English and many other languages, they are used to coin numerous series of words.

This timeline of binary prefixes lists events in the history of the evolution, development, and use of units of measure for information, the bit and the byte, which are germane to the definition of the binary prefixes by the International Electrotechnical Commission (IEC) in 1998.International Electrotechnical Commission (January 1999), IEC 60027-2 Amendment 2: Letter symbols to be used in electrical technology – Part 2: Telecommunications and electronics.

Each cell in this table contains a three-digit ZIP code prefix, the state where that ZIP code prefix is located, and the name of the United States Postal Service (USPS) Sectional Center Facility (SCF) that serves that ZIP code prefix, which may be in a different state. Each SCF may serve more than one three-digit ZIP code prefix.