Their a lot if difference between electronic money like bitcoin and physical money like real money. In case of real money you have to pay tax but in bitcoin their is no required to pay tax. In the transition of real money a third party (e.g. bank ) involved but in case bitcoin their no involvement of third party and its less traceable then real money. In the case  real money government has control in it but in the case of bitcoin government has no such control. In the case of real money it is difficult to convert into any other currency but in the matter of bitcoin it doesn't happen.