Lightning reaches 50,000 degrees Fahrenheit, fours times as hot as the sun's surface. Yet, unlike high voltage electrical injuries with which massive internal tissue damage may occur, lightning seldom causes substantial burns.
During the second half of the 18th century, Ben Franklin was the one who began the scientific study of lightning. He designed an experiment which conclusively proved the electrical nature of lightning. The experiment revealed that clouds are electrically charged so began his journey into lightning. Learn more here.