Tieguanyin is not green tea but a variety of oolong tea, according to the classification of tea oolong tea is green tea, semi-fermented tea. Green tea is not fermented. Oolong tea is also divided into Minbei oolong and Minnan oolong. Narcissus, Dahongpao, Cinnamon, etc. belongs to Minbei Oolong; Tieguanyin, Qilan, Narcissus, Golden Osmanthus, etc. belongs to Minnan Oolong. Tieguanyin is produced in Anxi County, Fujian Province, one of China's top ten famous teas, Tieguanyin is the best oolong tea, its quality characteristics are: tea curls, fat, round, heavy and even, color sand green, the overall shape of the dragonfly head, spiral, frog legs. After brewing, the soup color is golden and rich like amber, with natural fragrance of orchids, mellow and sweet taste, long sweet aftertaste, commonly known as "sound rhyme". Tieguanyin tea aroma is high and long-lasting, can be said to be "seven bubbles have aftertaste". But in recent years, Iron Goddess of Mercy has become a generic term for this type of tea, no longer refers to specific varieties, so now the "Iron Goddess of Mercy" is not a variety of Minnan oolong tea concept, and even became synonymous with Minnan oolong tea.