Yes, there are two official currencies used in Cuba. Yes, they are both called a peso. No, they are not the same.
The two currencies are called the Cuban Peso (CUP) and the Peso Convertible (CUC). Most tourists only do transactions in CUCs. For a long time, the U.S. dollar was an illegal second currency until it was finally legalized in 1993 and then replaced by the CUC.
The export of CUC is not allowed, so there is officially no CUC to buy outside of Cuba. If you’re flying into Cuba, you’ll need to bring your country’s currency in to be exchanged at the airport or somewhere else in Cuba. The CUC is pegged to the dollar in value, so you won’t need to do mental math gymnastics trying to calculate conversions at a shop or restaurant.
So, who uses the CUP? Most Cubans are paid in CUP. As you might have guessed, it is also worth considerably less than CUCs. While tourists travel through Cuba buying chips at hotel snack bars, they are paying for lunch what many Cubans earn in a month. CUPs are designed to purchase goods in state owned stores where all the goods are price-controlled.
However, many of the state run stores fail to keep many basic goods in stock. The system is wildly unpopular and advantages tourists rather than Cubans. Why? Put simply, Cuba’s entire economy today practically depends on tourism and remittances. There have been plans to unify the two currencies, but little action has been taken to fulfill such plans.