IF we buy a phone in USA for 100 $ and then buy the same phone in UK at the same time, would it not cost the same amount of money? Suppose we exchange the 100 $ to 80 UK pound, the same phone could be bought in UK for 80 pounds.... So WHY we need to go through all this exchanging? Why not adopt the same currency throughout the world?.....Different currency only changes the NUMBER but the 100 US$ is worth the same phone anywhere in the world...
Beacuse i thinkĀ it is dependent upon the countries languages.
french cannot understand indians language or neither indians can know french people. or countries nation.

and each currency have different values.