What is Money ? 

Something that has a real value and can be exchanged for a good or a service.
It can serve as a medium of exchange, a unit of account or a store of value.
Money at different times has been steel, gold, stones, cigarettes, goats, camels, oils and wheat.

The primary function of money is to be widely accepted in exchange for goods and services, provide a common measurement of the relative value of the goods and services and the ability to hold value over time.

Money itself provides no return, so people and businesses who hold cash or cheque account balances incur an opportunity cost (forgone interest).

We need money for three reasons. Transactions demand our daily needs spending, precautionary demand in case of an emergency and speculative demand for financial assets or investments.