International System of Units

The metric system (abbreviated to SMD) is the most widely used.

The metric system is said because it is derived from the Metro is the basic unit for length.

The other unit used to measure the areas, volumes, weights, and capabilities are derived from meters.

It is also said that every decimal units of measure and sub-multiples. The first are obtained by multiplying the basic units (meter, liter, kilogram, etc. ...) for 10, 100, 1000 and so on. The latter are obtained by dividing the basic units for 10, 100, 1000, etc. ..

And sub-multiples of the fundamental units are also known as secondary units.

The International System of Units (abbreviated SI from the French Système International d'Unités) is the modern form of the metric system and is Generally a system of units of measurement devised around seven base units and the convenience of the number ten. It is the World's Most Widely used system of measurement, Both in everyday commerce and in science.