Tea (from the tea plant Camellia Sinensis) is divided into six different main categories. The classification depends on the type of processing the tea leaves have undergone and can be broadly categorized by the degree of oxidation. These categories are attributed individual colors, which more or less vaguely also represent the liquid in the cup.

The two notable exceptions are blue tea and black tea. The level of oxidation of ‘blue tea’ is between that of green tea and black tea. Blue tea is never blue, except where some nifty sellers add a blue colorant to make the liquid look blue. When it comes to the classification of ‘black tea’, Westerners look at the dried black tea leaves whereas the Chinese consider the colour in the cup and thus identify it as ‘red tea’.