All true teas come from the same plant, Camellia Sinensis. The only difference between the over 3,000 varieties of tea in the world is how and when those leaves are picked and processed. The Camellia Sinensis plant provides us with black tea, green tea, oolong tea, white tea, and even Pu-er (a double-fermented tea). Red (Rooibos) tea, and Herbal teas are not really teas at all since they are not from the Camellia Sinensis plant, instead they are more aptly named “tisanes.”
There are two principal varieties of the Camellia Sinensis plant that produce tea leaves, the small-leaved China plant (C. sinensis sinensis) and the large-leaved Assam plant (C. sinensis assamica). Within those two varieties lies quite a few individual strains however, resulting in variances in flavor and aroma.