[1] Of all the different types, black teas usually contain the most caffeine. [2] There are many different varieties of tea. [3] So, if you're drinking tea late at night, you might want to choose a red or herbal tea instead of a black tea if you don't want to be kept awake by caffeine. [4] Teas can be grouped into a few major categories: black, green, white, red, and herbal teas. [5] On the other hand, red teas and herbal teas can be almost entirely caffeine-free.