Comment by zahrevsky

Not only bartering has never been the default mean of exchange, but also the idea that money were created to optimize the trading process is also wrong.

For an item to become currency in a society, it must already be something people value independently of its use as money, and people must expect others to accept it as well. Say the villagers live near the sea and find some beautiful shiny stones that everyone wants. Those stones can then become currency.

A good example of this is tobacco in colonial America. It came to be used as currency because it was already widely traded and valued.