Bubble tea is a Taiwanese tea-based drink invented in Tainan and Taichung in the 1980s. Recipes contain tea of some kind, flavors or milk, as well as sugar (optional). Toppings, such as chewy tapioca balls, popping boba, fruit jelly, grass jelly, agar jelly, and puddings are often added. Ice-blended versions are frozen and put into a blender, resulting in a slushy consistency. There are many varieties of the drink with a wide range of flavors. The two most popular varieties are black pearl milk tea and green pearl milk tea.