When it comes to the world’s most advanced currency, you might assume that it’s the Euro, British pound or even the US dollar, but surprisingly it’s not. According to the United Nations, there are 180 official currencies across the world , with these being used as legal tender in 195 countries across the world. While you might assume that the highest-value currency is the one that’s used most around the world, that isn’t actually the case. So, what actually determines how strong a currency is