units and measurement

[vivekananda behera]

we can measure with one system of unit
so,why there's many units like m.k.s units,s.i units,c.g.s units?

[jboggs]

For the same reason there are many different languages. Each culture developed their own system independent of any effects from other cultures. History.

[PinkertonD]

These days it doesn't matter. Modern CNC machines don't care about units. In the older machines one complete turn of a lead screw moved something a finite unit of measure and it was always difficult to convert Metric to Inch on machine tools. Today's machines don't care, they count encoder pulses.

http://www.onlineconversion.com/

[vivekananda behera]

thanx guies