Originating from Taiwan, "boba" specifically refers to chewy tapioca balls that serves as common topping for tea drinks, especially milk tea. To learn more about the development of boba, check out this interview with the inventor of boba, Lin Hsiu Hui.
In certain areas like the Bay Area, the term has become an umbrella reference to the tea drinks that are typically served with boba.
There are number of reasons why I have become obsessed with drinking boba over the years.
The combination of these factors have caused heavy damage to my wallet over the years. I drink boba at least once a week. Whenever I travel somewhere, I have to try the boba there. It is most likely a problem
Here's a compilation of some different drinks I've tried.