Descriptive tasting terms (like "citrus" or "caramel") used to describe what you might taste in a cup of coffee.
Flavour notes describe the tastes and aromas you might pick up in a cup - similar to how tasting notes work for wine or whisky. They come from a coffee's origin, processing method, and roast, and are meant as a guide to what to expect rather than a guarantee of what you'll taste, since palates and brewing methods vary.