# Nano-

Nano (symbol n) is a unit prefix meaning one billionth. Used primarily with the metric system, this prefix denotes a factor of 10$^{−9}$ or 0.000000001. It is frequently encountered in science and electronics for prefixing units of time and length.

## Examples

* Three gold atoms lined up are about one nanometer (nm) long.
* If a toy marble were scaled down to one nanometer wide, Earth would scale to about 1 meter (3.3 ft) wide.
* One nanosecond (ns) is about the time required for light to travel 30 cm in air, or 20 cm in an optical fiber.
* One nanometer per second (nm/s) is approximately the speed that a fingernail grows.
The prefix derives from the Greek νᾶνος (Latin nanus), meaning "dwarf". The General Conference on Weights and Measures (CGPM) officially endorsed the usage of nano as a standard prefix in 1960.
When used as a prefix for something other than a unit of measure (as for example in words like "nanoscience"), nano refers to nanotechnology, or means "on a scale of nanometres" (nanoscale).
SI prefixesvte :
| Prefix | Prefix | Base 10 | Decimal | Adoption |
| Name | Symbol | Base 10 | Decimal | Adoption |
| quetta | Q | 10$^{30}$ | 1000000000000000000000000000000 | 2022 |
| ronna | R | 10$^{27}$ | 1000000000000000000000000000 | 2022 |
| yotta | Y | 10$^{24}$ | 1000000000000000000000000 | 1991 |
| zetta | Z | 10$^{21}$ | 1000000000000000000000 | 1991 |
| exa | E | 10$^{18}$ | 1000000000000000000 | 1975 |
| peta | P | 10$^{15}$ | 1000000000000000 | 1975 |
| tera | T | 10$^{12}$ | 1000000000000 | 1960 |
| giga | G | 10$^9$ | 1000000000 | 1960 |
| mega | M | 10$^6$ | 1000000 | 1873 |
| kilo | k | 10$^3$ | 1000 | 1795 |
| hecto | h | 10$^2$ | 100 | 1795 |
| deca | da | 10$^1$ | 10 | 1795 |
| — | — | 10$^0$ | 1 | — |
| deci | d | 10$^{−1}$ | 0.1 | 1795 |
| centi | c | 10$^{−2}$ | 0.01 | 1795 |
| milli | m | 10$^{−3}$ | 0.001 | 1795 |
| micro | μ | 10$^{−6}$ | 0.000001 | 1873 |
| nano | n | 10$^{−9}$ | 0.000000001 | 1960 |
| pico | p | 10$^{−12}$ | 0.000000000001 | 1960 |
| femto | f | 10$^{−15}$ | 0.000000000000001 | 1964 |
| atto | a | 10$^{−18}$ | 0.000000000000000001 | 1964 |
| zepto | z | 10$^{−21}$ | 0.000000000000000000001 | 1991 |
| yocto | y | 10$^{−24}$ | 0.000000000000000000000001 | 1991 |
| ronto | r | 10$^{−27}$ | 0.000000000000000000000000001 | 2022 |
| quecto | q | 10$^{−30}$ | 0.000000000000000000000000000001 | 2022 |
| Notes ↑ Prefixes adopted before 1960 already existed before SI. The introduction of the CGS system was in 1873. |||||

## Nanometre

X-rays have a wavelength ranging from the size of 0.01 nm to 10 nm.
Human fingernails grow at approximately one nanometer per second.

## Nanosecond

A nanosecond (ns) is a unit of time in the International System of Units (SI) equal to one billionth of a second, that is, 1⁄1 000 000 000 of a second, or 10$^{−9}$ seconds.
The term combines the SI prefix nano- indicating a 1 billionth submultiple of an SI unit (e.g. nanogram, nanometre, etc.) and second, the primary unit of time in the SI.
A nanosecond is to one second, as one second is to approximately 31.69 years.
A nanosecond is equal to 1000 picoseconds or 1⁄1000 microsecond. Time units ranging between 10$^{−8}$ and 10$^{−7}$ seconds are typically expressed as tens or hundreds of nanoseconds.