Rial (IRR), first introduced in 1798, is official Iran’s currency. However, the Persians prefer to express the amount of money and prices in “Tomans”. Each toman equals 10 rials, or put it in another word, each rial has one zero more than toman.
The tourist can exchange their money for rials in official money exchange places without any problem. These places are called Sarrafi. All have a board or monitors in which the currency exchange and prices are shown.