The official language of Cuba is Spanish, very similar to the Spanish of the Dominican Republic and Puerto Rico, although the version here is very different from that spoken in Spain (although it is quite similar to that spoken in the Canary Islands, as many Cubans are descendants of Canarians), Mexico and South America. Cubans tend to swallow the last syllable of a word, usually the “s” sound.
Basic or correct English is spoken in some tourist locations and the language should not be a barrier to visiting the country for non-Spanish speaking tourists who can speak English, although a basic knowledge of Spanish can be useful, especially in more informal situations. Cubans love to talk to tourists, especially if you stay with them in “casas particulares”, and some knowledge of Spanish will help you understand the experiences of ordinary Cubans.
Instead of the Spanish “Que tal?” for “How are you?” Cubans say “Que vola?” (similar to “What’s up?”, usually quite informal) or “Como andas? (similar to “What’s up?”, usually quite informally) or “Como andas?” (literally means “How do you go?”). Young Cubans use the word “asere” among themselves, which means “buddy”, but is generally used between men and is not recommended for women.