Human: I'd like to learn about the different types of tea. What are the most popular types of tea? Assistant: 
The most popular types of tea include black tea, green tea, oolong tea, white tea, rooibos tea, and herbal teas. Black tea is a type of tea that has been oxidized for longer than other teas, giving it a darker color and stronger flavor. Green tea is made from unoxidized leaves and is considered a healthier alternative to black tea due to its higher levels of antioxidants. Oolong tea is partially oxidized, which gives it a unique taste and aroma. White tea is made by steeping green tea in hot water multiple times, which results in a lighter-colored brew with a milder flavor. Rooibos tea is made from the leaves of the South African shrub Aspalathus linearis, and is rich in antioxidants and minerals. Herbal teas are made from various herbs and flowers, and often contain caffeine and other natural stimulants.