According to what we know money has been in existence for a long time. In ancient Greece the coins issued were made of a metal known as electrum. The value of the coin was the same as its weight; the bigger the coin the more valuable it was.
Other societies developed different currencies. In some places the cowrie acted as money, in others it was the cow. The Roman soldiers who were living far away from Rome were paid in salt because salt was not commonly available. The English word ‘salary’ comes from the custom of making payments in salt.
Money works because, as members of society, we all agree that it should work; outside of society money does not make sense. Imagines if you were alone on an island and you saw two boxes in the sea. One box contains millions of dollars, the other box contains various tools such as a saw, knives, etc., and agricultural seeds. You anly have time to remove one box because the tide is carrying them away. Which box would you hold on to?