Kilo-
From Wikipedia, the free encyclopedia
Wiktionary, the free dictionary.
Kilo- (symbol: k) is a prefix in the SI and other systems of units denoting 103 or 1,000. For example:
- one kilogram is 1,000 grams
- one kilometre is 1,000 metres
- one kilowatt is 1,000 watts
- one kilojoule is 1,000 joules
Officially adopted in 1795 (though in common use before that), it comes from the Greek χίλιοι ("khilioi"), meaning thousand.
| 1000n | 10n | Prefix | Symbol | Since[1] | Short scale | Long scale | Decimal equivalent in SI writing style |
|---|---|---|---|---|---|---|---|
| 10008 | 1024 | yotta- | Y | 1991 | Septillion | Quadrillion | 1 000 000 000 000 000 000 000 000 |
| 10007 | 1021 | zetta- | Z | 1991 | Sextillion | Trilliard (thousand trillion) | 1 000 000 000 000 000 000 000 |
| 10006 | 1018 | exa- | E | 1975 | Quintillion | Trillion | 1 000 000 000 000 000 000 |
| 10005 | 1015 | peta- | P | 1975 | Quadrillion | Billiard (thousand billion) | 1 000 000 000 000 000 |
| 10004 | 1012 | tera- | T | 1960 | Trillion | Billion | 1 000 000 000 000 |
| 10003 | 109 | giga- | G | 1960 | Billion | Milliard (thousand million) | 1 000 000 000 |
| 10002 | 106 | mega- | M | 1960 | Million | 1 000 000 | |
| 10001 | 103 | kilo- | k | 1795 | Thousand | 1 000 | |
| 10002/3 | 102 | hecto- | h | 1795 | Hundred | 100 | |
| 10001/3 | 101 | deca- | da | 1795 | Ten | 10 | |
| 10000 | 100 | (none) | (none) | NA | One | 1 | |
| 1000−1/3 | 10−1 | deci- | d | 1795 | Tenth | 0.1 | |
| 1000−2/3 | 10−2 | centi- | c | 1795 | Hundredth | 0.01 | |
| 1000−1 | 10−3 | milli- | m | 1795 | Thousandth | 0.001 | |
| 1000−2 | 10−6 | micro- | µ | 1960[2] | Millionth | 0.000 001 | |
| 1000−3 | 10−9 | nano- | n | 1960 | Billionth | Milliardth | 0.000 000 001 |
| 1000−4 | 10−12 | pico- | p | 1960 | Trillionth | Billionth | 0.000 000 000 001 |
| 1000−5 | 10−15 | femto- | f | 1964 | Quadrillionth | Billiardth | 0.000 000 000 000 001 |
| 1000−6 | 10−18 | atto- | a | 1964 | Quintillionth | Trillionth | 0.000 000 000 000 000 001 |
| 1000−7 | 10−21 | zepto- | z | 1991 | Sextillionth | Trilliardth | 0.000 000 000 000 000 000 001 |
| 1000−8 | 10−24 | yocto- | y | 1991 | Septillionth | Quadrillionth | 0.000 000 000 000 000 000 000 001 |
| Notes: 1. The 1795 dates identify prefixes in use since the metric system was introduced. The other dates are not necessarily dates of first use, but rather the date of recognition by a resolution of the CGPM, which first met in 1889. 2. The micron was earlier recognized by the CGPM in 1948; that decision was abrogated in 1967-68. | |||||||
[edit] Use in computing
In binary computing, kilo does not always denote 1,000 but is sometimes equal to 1,024 (210), most often when discussing memory and file sizes. See binary prefix for more details.ar:كيلو br:Kilo ca:Kilo cs:Kilo da:Kilo- et:Kilo- es:Kilo (acepciones) fa:کیلو fr:Kilo gl:Quilo ko:킬로 id:Kilo- it:Kilo (prefisso) he:תחיליות במערכת היחידות הבינלאומית#.D7.A7.D7.99.D7.9C.D7.95 ku:Kîlo ln:Kilo nl:Kilo (SI-prefix) ja:キロ no:Kilo nn:Kilo nds:Kilo pl:Kilo pt:Quilo ru:Кило- sk:Kilo sl:Kilo sr:Кило fi:Kilo ta:கிலோ vi:Kilô tr:Kilo uk:Кіло
