Oolong/Wulong is one of the six main classes of Chinese teas. Oolong teas are semi-fermented and therefore sit between the unfermented green teas and fully fermented black teas. There are many members in this family. Fermentation is a crucial determinant during the process of tea making and various Oolong teas are fermented to different levels. For example Tie Guan Yin is about 20% fermented, while Da Hong Pao is about 85%. In conjunction with other variants such as tea plants and different tea making techniques, the members of this family present a vast degree of variation in both their appearance and taste.