The two main porducers of quality green teas, China and Japan, differ on their prefered method of manufacture. The Chinese tend toward pan-fired teas, meaning the leaves are heated via a wok-like pan to arrest enzyme activity inside the leaf (try our Lung Ching Dragonwell and Lung Ching Special Grade for the most famous example) Appearance is important to Chinese teas. While the leaf is being fired the leaves will be shaped and formed, often by hand into whatever the desired form is, flattened, curled or as in the case of the Pinhead Gunpowder rolled into tight balls.
The Japanese prefer to steam their leaves then press them flat (appearance is less important here, consistency is the goal). Steaming creates a tea that is bright in color and taste. The Gyokuro Jade Dew is Japan's most honored tea, made from bushes kept in the shade.