Engineering notation is scientific notation in which the powers of ten are limited to those where the exponent is a multiple of three, i.e, the powers are powers of 1000 (but written as e.g. 10⁶, not 1000²). In scientific notation numbers are written as where is the integer exponent and the coefficient is any real number and is called the significand or the mantissa (using mantissa may cause confusion as it can also refer to the fractional part of the common logarithm). ... In mathematics, exponentiation (frequently known colloquially as raising a number to a power) is a process generalized from repeated (or iterated) multiplication, in much the same way that multiplication is a process generalized from repeated addition. ... 10 (ten) is an even natural number following 9 and preceding 11. ... 3 (three) is a number, numeral, and glyph. ...

As an alternative for writing powers of 10, SI prefixes can be used. These also provides steps of a factor 1000, except if the unit has an exponent: in that case the SI prefixes provide only steps of a factor one million, one billion, or more. An SI prefix is a prefix that can be applied to an SI unit to form a decimal multiple or submultiple. ...

A disadvantage both of using an SI prefix and of using engineering notation, compared with scientific notation, is that e.g. 500 µm and 500 × 10⁻⁶ m do not show the accuracy distinction between 5 × 10⁻⁴, 5.0 × 10⁻⁴, and 5.00 × 10⁻⁴ m. That can be solved by not using a range 1–1000 for the number in front of the power, but a number in the range 0.01–10. Depending on the case this may be suitable, or impractical. In the example we can use 0.5, 0.50, and 0.500 mm.

Another example: when the speed of light (defined as 299 792 458 m/s) is expressed as 3.00 × 10⁸ m/s or 3.00 × 10⁵ km/s then it is clear that it is between 299 500 and 300 500 km/s, but when using 300 × 10⁶ m/s, or 300 × 10³ km/s, 300 000 km/s, or the unusual but short 300 Mm/s, this is not clear. A possibility is using 0.300 Gm/s, convenient to write, but somewhat impractical in understanding (writing something large as a fraction of something even larger; in a context of larger numbers expressed in the same unit this could be convenient, but that is not applicable here). The speed of light in a vacuum is denoted by the letter c. ...

An SI prefix is a prefix that can be applied to an SI unit to form a decimal multiple or submultiple. ... // Short scale is the English translation of the French term échelle courte, which designates a system of numeric names in which the word billion means a thousand millions. ... // Short scale is the English translation of the French term échelle courte, which designates a system of numeric names in which the word billion means a thousand millions. ... The decimal (base ten or occasionally denary) numeral system has ten as its base. ... Yotta (symbol Y) is a SI prefix in the SI (system of units) denoting 1024 or 1 000 000 000 000 000 000 000 000. ... Main article: Names of large numbers A septillion is a number written as either: a 1 followed by 24 zeros (10 to the 24th power, as used in the short scale system of numeration. ... The quadrillion is a large number which has one of two values depending on how or where it is being used. ... Zetta (symbol Z) is a SI prefix in the SI (system of units) denoting 1021 or 1 000 000 000 000 000 000 000. ... Main article: Names of large numbers A sextillion is a number written as either: a 1 followed by 21 zeros (10 to the 21st power, as used in the short scale system of numeration. ... In long scale usage: one trilliard = 1,000,000,000,000,000,000,000 = 1021 one thousand trilliards =one (long scale) quadrillion This word is not found in standard English dictionaries. ... In the X Window System, in the X.Org Server, EXA is a graphics acceleration architecture to make the XRender extension more usable, with only minor changes needed to adapt XFree86 video drivers written to use XAA (the XFree86 Acceleration Architecture). ... Main article: Names of large numbers A quintillion is a number written as either: a 1 followed by 18 zeros (10 to the 18th power, as used in the short scale system of numeration. ... The numeral trillion refers to one of two number values, depending on the context of where and how it is being used. ... In physics and mathematics, peta- (symbol: P) is a prefix in the SI (system of units) denoting 1015, or 1 000 000 000 000 000. ... The quadrillion is a large number which has one of two values depending on how or where it is being used. ... In some countries and languages using the long scale: one billiard = = one short scale quadrillion. ... tera- (symbol: T) is a prefix in the SI system of units denoting 1012, or 1 000 000 000 000. ... The numeral trillion refers to one of two number values, depending on the context of where and how it is being used. ... The word billion and its equivalents in other languages refer to either one million million or one thousand million, depending on whether the writer is using the long scale or the short scale. ... giga- (symbol: G) is a prefix in the SI system of units denoting 109, or 1 000 000 000. ... The word billion and its equivalents in other languages refer to either one million million or one thousand million, depending on whether the writer is using the long scale or the short scale. ... Milliard is a French-derived word meaning the number 109. ... mega- (symbol M) is an SI prefix in the SI system of units denoting a factor of 106, i. ... One million (1,000,000), or one thousand thousand, is the natural number following 999,999 and preceding 1,000,001. ... Kilo (symbol: k) is a prefix in the SI system denoting 103 or 1000. ... Cardinal 1000 one thousand Ordinal 1000th Numeral system Factorization Prime Divisor(s) Roman numeral Unicode symbol(s) , , Greek Prefix chilia Latin Prefix milli Binary 1111101000 Octal 1750 Duodecimal 6B4 Hexadecimal 3E8 1000 (one thousand) is the natural number following 999 and preceding 1001. ... Hecto (symbol h) is a SI prefix in the SI system of units denoting a factor of 102 (100). ... 100 (one hundred) (the Roman numeral is C for centum) is the natural number following 99 and preceding 101. ... For the marketing association, see DECA (Organization) For the research company, see DEKA. Deca- (U.S. spelling deka, Greek δέκα) is a Greek prefix meaning ten. ... 10 (ten) is an even natural number following 9 and preceding 11. ... Look up one in Wiktionary, the free dictionary. ... deci- (symbol d) is a prefix in the SI system of units denoting a factor of 10−1 (1/10). ... Centi (symbol c) is a SI prefix in the SI system of units denoting a factor of 10-2, or 1/100. ... Milli (symbol m) is an SI prefix in the SI system of units denoting a factor of 10-3, or 1/1,000. ... Micro is a SI prefix in the SI system of units denoting a factor of 10−6 (one millionth). ... Nano is a noun Name for an Apple Brand Ipod available in 2GB and 4GB memory sizes whose purpose is for storing and playing music. ... For other meanings of Pico see Pico (disambiguation) Pico (symbol p) is a prefix in the SI system of units denoting a factor of 10-12. ... Femto is an SI prefix (symbol f) in the SI system of units denoting a factor of 10−15 or 0. ... Atto- (symbol a) is an SI prefix to a unit and means that it is 10-18 times this unit. ... Zepto (symbol z) is a prefix in the SI system of units denoting a factor of 10-21. ... Yocto (symbol y) is a SI prefix in the SI system of units denoting a factor of 10-24. ...

See also

• SI
• Significant figures