Black tea, more commonly known as "red" tea throughout the world, is a tea born of necessity. In the early days of tea trade, the green teas of China often spoiled as they made their way from Asia to England by sail. The roasting of black teas helped preserve them during the long voyage. Black teas get their characteristc flavor and color from the oxidation process that follows the rolling and drying of the leaves. Studies have shown black tea has a higher presence of caffeine then green tea, but is rich in antioxidants.