Kinds of tea and japanese green tea
(Marukyu Koyamaen site – various kinds of Japanese green teas as well as an Oolong and a black tea: for comparison.)

All teas, whether they are green, black or of the so-called oolong type are made from the same plant, Camellia sinensis. The difference between these types of teas depends on whether they have been fermented or not, and if the former is the case, how much they have been fermented. Green teas are not fermented.

Tea (camellia sinensis):
– Green tea (non-fermented)
– Oolong tea (semi-fermented)
– Black tea (fully fermented)