Garifuna is an Arawakan language that originated on the island of St. Vincent, but is now spoken in Belize, Nicaragua, Honduras, and Guatemala. The Garinagu (also known as Black Carib) number roughly 250, 000 with the majority living in Honduras.
I have seen many places where Garifuna is called a creole but this is not the case. While the Garifuna language does contain borrowings from English, French and Spanish, and of course Galibi, it is solidly an Arawakan language. In addition, only one word of African origin is in the Garifuna language, mutu meaning "person".
The Garifuna language is very very closely related to the Karifuna though there are differences, mainly in terms of pronunciation and stress but also sentence structure. In spite of these differences a person speaking and Karifuna and a person speaking Garifuna could understand each other without difficulty.
Pronunciation notes: In Garifuna most letters are sounded as in Spanish, except for "h" which is like it's English counterpart and "ü" which is a sound that is found in many indigenous South American languages but not in English. To produce this sound say the "oo" sound as in the word "pool" and then unround your lips while saying it.