Black Tea and Doppio are produced all around the globe. And they change according to region in where they are cultivated. So, the question arises what is Black Tea and Doppio's differentiating factor?In following section we will take a close look at what is Black Tea and Doppio color, serving style, types and much more. First thing to know is what are the different types of Black Tea and Doppio. Well, Black Tea types include Tanyang Gongfu, Zhenghe Gongfu, Zhengshan xiaozhong, Earl Grey Tea while types of Doppio are Espresso.