Oolong 乌龙茶 - Black Tea 紅茶
Black and oolong, or wūlong, teas are crafted using similar processes of withering, rolling, shaping and firing but it's the amount of oxidation that gives each tea it's unique character. Oxidation can range from 8 - 85% for oolong and typically higher for black tea.
It's said that after a long day of picking tea leaves, a man named Wu Liang was distracted by a deer and forgot about his harvest. By the time he came back to his basket, the leaves had begun to oxidize thus, the origins of wulong tea.