The best way to understand about wine and its flavours is learn about grape variety. Each different grape varietal has its own hallmark flavours; so two wines made with the same variety produced in vineyards thousands of miles apart will have similar flavour characteristics.
Not all wines are made from a single grape variety. Red Bordeaux, for example, usually contains at least three. However, once you know the taste of different grapes you should know what to expect from a blend.