Pu'er tea is a post-fermented tea, mainly produced in Yunnan. It is divided into "raw Pu'er" and "ripe Pu'er". Raw Pu'er is naturally fermented after fresh leaves are fixed, with a strong tea nature and a bitter taste followed by a sweet aftertaste. Ripe Pu'er is artificially fermented through pile fermentation, with a mild nature, a mellow and smooth taste, and an aged aroma. Pu'er tea is known for "improving with age" and is suitable for long-term storage.