The boba in boba tea, also known as bubble tea, is made of tapioca. These bubbles or "pearls" are made from the root of the cassava plant, which originated in South America and is now cultivated worldwide.
Boba tea first became popular in Taiwan in the 1980s. Properly cooked boba pearls are soft and chewy. Sweet potato or another starch is often added to the black boba pearls, as is some amount of sugar. White boba pearls often use chamomile root and caramel instead. Boba are usually served in black or green tea, often with milk and various fruit flavors mixed in.