0!=1.........why????

My queation is that why 0! is equal to 1.Can you prove this?....Lr mr try..I know there will be a smile on your face because this is a very stupid way to prove this?

You know  
                      n!=n*(n-1)!
This implies                    
                      n!/(n)=(n-1)!
put n=2   then
                            
                      2!/2=1!=1     is this right? .....yes

now put n=1
                   then 1!/1=0!=1  
                 
So 0!=1 is proved. I know that it is a very stupid way but not to much bad.