Editing Unit of length (section)

==Metric system==
{{main article|Metric system}}

===SI===
{{main article|International System of Units}}
{{See also|Orders of magnitude (length)}}
The [[SI base unit|base unit]] in the International System of Units (SI) is the [[meter]], defined as "the length of the path travelled by [[speed of light|light]] in vacuum during a time interval of {{frac|299792458}} seconds."<ref name="Res1">{{cite web |url=http://www.bipm.org/en/CGPM/db/17/1/ |title=17th General Conference on Weights and Measures (1983), Resolution 1. |access-date=2012-09-19}}</ref> It is approximately equal to {{val|1.0936|u=yards}}. Other SI units are derived from the meter by adding [[Metric prefix|prefixes]], as in millimeter or kilometer, thus producing systematic decimal multiples and submultiples of the base unit that span many orders of magnitude. For example, a [[kilometer]] is {{val|1000|u=meters}}.

===Non-SI===
In the [[centimetre–gram–second system of units|centimeter–gram–second system of units]], the basic unit of length is the [[centimeter]], or {{frac|100}} of a meter.
Other non-SI units are derived from decimal multiples of the meter.
{| class="wikitable" style="margin-left: 20px;" background-color: #ffffff"
! Name
! Symbol
! SI value
|- align="left"
| fermi
| aligh="center" | fm
|1 [[femtometer]]
|-
| [[ångström]] 
| Å
| 100 [[picometer]]s
|-
| micron
| μm
| 1 [[Micrometre|micrometer]]
|-
| [[Norwegian/Swedish mil]] or [[myriameter]]
| 
| 10,000 meters
|-
| [[x unit]] 
| xu
| 0.1 picometer
|}