The Metric System
The metric system is a system of measurement based on the powers of 10. First adopted in France in 1791, the metric system has become widely used in many countries of the world, and is the main system used in science.
The basic metric unit of length is the meter, equal to about 3.28 feet. Some smaller and larger units are named as follows:
| nanometer(nm) |  of a meter |
| micrometer(um) |  of a meter |
| millimeter(mm) |  of a meter |
| centimeter(cm) |  of a meter |
decimeter(dm) |
|
meter(m) |
|
dekameter(dam) |
10 meters |
hectometer(hm) |
100 meters |
kilometer(km) |
1000 meters |
Megameter(Mm) |
1,000,000 meters |
Gigameter(Gm) |
1,000,000,000 meters |
Terameter(Tm) |
1,000,000,000,000 meters |
of a meter
The same prefixes are used for other units. For example, 1 kilogram is equal to 1000 grams (a unit of mass), and 1 centiliter is equal to of a liter (a unit of volume).
Other metric units include the newton (a unit of force), the pascal (a unit of pressure), the watt (a unit of power), the joule (a unit of energy), and the ampere (a unit of electric current).
