Turkey use Lira for money currency. The biggest money is 200 lira which make more less 100 Euro or 130 USD. Ofcourse Turkish lira is most popular money to use in country but many places accept euro US dolar or english pounds. Better wait until you get to Istanbul to exchange money for Turkish Liras. Exchange rates outside of Turkey are usually not as good as those inside Turkey. In Istanbul Kapali Carsi (Grand Bazaar) is offer a best rates for exchange your money. The best currencies to carry for changing to Turkish lira are,  euros, US dollars, and UK pounds.