### SI

**(International System of Units)**
(modern metric system)

**SI** indicates the **International System of Units**,
a current, widely-accepted system of the metric units,
standardized internationally and overseen by international organizations.
The system includes refined definitions for a basic set of units
(meter, kilogram, second, kelvin, mole, and candela)
and an extensive set of more specialized units derived from these.
The common metric units (e.g., meter, kilogram) predate the system
and are also used in other similar metric-based systems.

Some non-SI units remain in common use, especially for electromagnetic
measurement, such as for magnetic flux density: in addition to
the SI unit, the tesla, a non-SI (CGS) unit, the gauss,
is still in use.

(*measurement*)
http://en.wikipedia.org/wiki/International_System_of_Units

**Referenced by:**

CGS

gauss (G)

Julian date (JD)

joule

jansky (Jy)

magnetic flux (B)

magnetic flux density (B)

solid angle (Ω)

Stefan-Boltzmann constant (σ)

tesla (T)

time standard

terrestrial time (TT)

watt (W)

index