Kahlua is a coffee liqueur that can be used in many ways. As some may drink it on the rocks with vodka "black Russian" more popularly, some may add milk making it a "white russian" or it can be used in various shooters.
This is delicious on a hot summer day! I like to serve it chilled with some fruit such as raspberries, blackberries and strawberries thrown in. (I prefer frozen because they almost serve as am ice cube to help keep your drink cold) and can eat the fruit after :)