Tea is the most consumed drink in the entire world, coming second only to water. No matter the flavor, all teas come from the same sub-tropical, evergreen plant called the Camellia Sinensis. The various styles of tea are produced by altering the shape and chemistry of the leaf through 5 basics steps; plucking, withering (allowing leaves to soften and wilt), rolling (to shape leaves and extract juices), oxidizing (interacting the enzymes in tea with oxygen), and firing (drying). A combination of these steps create Black, Oolong, Pu'erh, Green, and White teas alike.
Despite the name Herbal tea, this beverage is not actually a "tea". It is made up of preserved fruits, dried flowers, and other herbs steeped in water, they are better known by experts as Tisanes, a French word for "herbal infusions". No tea leaves are actually included.