**SI is one of the largest system of unit. It has many advantages over other system of units like MKS or FPS or CGS.**

1. SI is a coherent system of units i.e. a system based on a certain set of fundamental units, from which all derived units are obtained by multiplication or division without introducing numerical factors i.e. units of a given quantity are related to one another by powers of 10.

2. SI is a rational system of units, as it assigns only one unit to a particular physical quantity.

3. SI is an absolute system of units. There are no gravitational units on the system. The use of factor ‘g’ is thus eliminated.

4. SI is an internationally accepted system