Dark sorcery, more commonly known as "witchcraft" or "Morgul magic" by the Free People of Middle-earth, was art of practicing dark magic for evil purposes. Famous practitioners of dark sorcery are mostly dark servants of the infamous Dark Lords Melkor and Sauron. It's users, as well as all human pracititioners of magic, were called Sorcerers. The Istari used light magic, similar to the Elves and the Ainur in Valinor and outside of Arda, rather than dark sorcery.