It is extremely useful in our lives. Without money , we would be forced to trade eggs for shoes in the terribly awkward and slow process of barter. Our economy would come to a screeching halt. Money represents value which represents real things such as human labor. This enables us to trade amounts of money which represents value instead of actually trading eggs for shoes.
Currency speeds up the process, making it faster and easier.
Money is NOT currency . Currency is NOT money . That is the second concept to grasp. Currency merely represents money. Since money is unreal, it would be convenient to have something real to represent it.