Cuba has two currencies though the government is in the process of unifying them. At the time of writing, convertibles (CUC$) and pesos (moneda nacional; MN$) were both still in circulation. One convertible is worth 25 pesos. Non-Cubans deal almost exclusively in convertibles.
Tipping in Cuba is important. Since most Cubans earn their money in moneda nacional (MN$), leaving a small tip of CUC$1 (MN$25) or more can make a huge difference.
Resorts/Hotels Tip for good service with bellboys, room maids and bar/restaurant staff.
Musicians Carry small notes for the ubiquitous musicians in restaurants. Tip when the basket comes round.
Tour guides Depending on tour length, tip from a dollar for a few hours to more for extensive guiding.
Restaurants Standard 10%, or up to 15% if service is excellent and/or you’re feeling generous.
Taxis Tip 10% if you are on the meter, otherwise agree full fare beforehand.