Difference between controlling area currency & company code currency?

Ans)For Currency their are two case are their:

Case I :-
 if Cocode =  Coarea then Currency of Cocode is equal to    
Controlling Area. 

Case II :-

If Cocode is not Equl to Coarea then it is called as cross 
company code. in this case u can assign one or more 
currency . 

coarea currency may be different  than in cocode currency

At the time of Maintain controling area we give company 
code currencey 10

Inthe currency field we give 10 all basic setting comes 
automatically

Both are the same

In the maintain controlling area we shoulg be give the 
company code currency