FIAT money is a currency that is not based on material goods (such as gold). The value of fiat money usually comes from political regulations. It has value maintained by governments or because parties agreed on its exchange value.
Fiat money originally appeared in China in the 11th century and started to dominate in the 20th century. After Richard Nixon decoupled US Dollar from gold in 1971, fiat currencies started to be used globally.Unlike cryptocurrencies, FIAT money is controlled by financial insitutions and may greatly lose its value due to hyperinflation.