What kinds of tea are there?

Looking at processing methods (actually, degree of oxidation), there are six types of tea:

Black tea, also known as red tea in Chinese – this is fully oxidised.

Green tea – this refers to barely oxidised (oxidation starts from the moment you pluck the leaf so I won’t say it’s 9% oxidised) tea that also goes through withering process(withering = remove excess water). We can think of green tea as being minimally processed.

White Tea – the least processed type of tea, all you do here is dry the leaves.

Oolong tea/blue tea – Oolong is a broad category referring to partially oxidised teas. There is no set percentage of oxidations which is why some oolongs are closer to green teas while others are closer to black teas.

Yellow teas – Yellow teas are pretty rare but basically, there is a period of yellowing the leaves (they place it in a heap and let the heat do its work) to mellow it out further. It’s got a slightly nutty note, compared to green tea, in my experience

Dark tea, also known as black tea in Chinese – these are teas which have been post-fermented (i.e. has good mold growing on them, like blue cheese). Puer is probably the most famous example (though some people are campaigning to make puer it’s own category) but there are post-fermented teas outside of China too, like the Goishicha tea from Japan.

I’d also like to point out another “type” of tea, which is aged tea. Two teas that are commonly ages are white teas and raw puer (raw puer = puer that is not fermented) and these teas tend to increase in price the longer they’ve been aged. There is even a saying: 一年茶 三年药 七年宝 (one year tea, three years medicine, seven years treasure).