We need something we can get our hands on to use in our daily lives. So, we used our human mind and invented currency to represent money. Now we have something real that we can hold in our hands and use to exchange value. But beware of a pitfall. It is much too easy to start calling currency money, and that is where we get into a heap of economic trouble.
People get to thinking that printing currency is printing money, but that is far from the truth.
Currency is printed on paper or minted from cheap metal. Money is created , not printed. We can't print something that is imaginary. By their own words, banklords create money by making an entry in a ledger, usually in a computer. When you get a loan from your bank, the banker enters the loan amount in his ledger.