Tom Greco argues that the problem of money is that it has been monopolised and mis-allocated. There is a misconception that we only pay interest when we borrow money, but the price paid for almost every item we buy includes a certain amount of interest. The interest component varies according to the amount of capital invested in the goods and services purchased. Usually when people think of money they only think about notes and coins that are circulating but this is only part of money.
Most money takes the form of electronic transfers, cheques, and bank accounts.
In earlier times useful commodities such as salt, cattle, and tobacco have been used as a medium of exchange. Precious metals later became widely used as money. More recently it became common to use notes and base metal coins to represent these precious metals. The holder of such notes could exchange them for the metal they represented. Money was invented to avoid the alleged flaw of the first method of trade, bartering.