Cocoa was used as a form of money in some parts of Mesoamerica in the past. It served as a medium of exchange, store of value, and unit of account. However, when coins became more popular, cocoa was no longer as effective as money. This shows how different forms of money can come and go over time. The study discusses how cocoa met the criteria for being a type of money in history, but was eventually replaced by other forms of currency.