System of fundamental units.

 Systems of Fundamental Units :

1. CGS System. In this systems, the unit of length is centimetre, the unit of mass is gram and the unit of time is second.

1m = 100 cm  or  1cm = 1/100 m.
1kg = 1000g   or   1g = 1/1000 kg.
1second =1/86400th part of a day.

2. FPS System. In this system, the unit of length is foot, the unit of mass is a pound and unit of time is second.

1 foot  = 12 inch = 12 x 2.54 cm = 30.48 cm
1 pound = 453 g = 0.453 kg.

3. MKS System. In this system the unit of length is metre, the unit of mass is kilogram and the unit of time is second.

4. SI Units. French name of this system is System International de Units  while in English SI stands for International System of Units. This system is an improved and extended version of MKS system of units.
This system is based on seven base and two supplementary units.

Base Units:
1. Length  -  metre (m).
2. Mass  -  kilogram (kg).
3. Time   -  second (s).
4. Electric current   -  ampere (A).
5. Luminous intensity   -  candela (Cd).
6. Temperature  - kelvin (K).
7. Amount of substance   -  mole (mol).

Supplementary Units:
1. Plain angle  -  radian (rad).
2. Solid angle   -  steradian (sr).