Understand
Before the Communist revolution, Havana was one of the vacation hot-spots of the Caribbean, and since Cuba reopened to tourism in the 1990s, it has become a popular destination once again, albeit with many fewer U.S. citizens, due to an almost total ban on travel maintained by the U.S. federal government. However, there will be lots of tourists at any time of year, so expect huge crowds and long lines in places.
El Habanero (http://elhabanero.cubaweb.cu) and Tribuna de La Habana (http://www.tribuna.islagr...) are the local periodicals. The H Magazine + Guide (http://www.thehmagazine.com) is an interesting publication about Havana beyond common stereotypes.
Currency
Cuba has two currencies, the Cuban Peso CUP and the Cuban Convertible Peso CUC. Most tourists will be using the CUC for all purchases, hotels, taxis and activities. The CUC was created to replace all the US$ that was used in the tourist industry until the late 1990s.
For more information check the section on Money in the Cuba article.