Defence Against the Dark Arts [Thrid Floor]

Defense Against the Dark Arts, also known as D.A.D.A., is a class taught at Hogwarts School of Witchcraft and Wizardry that focuses on defensive techniques to block spells, charms, curses, hexes, and jinxes cast by other wizards and witches, counteract the Dark Arts, and to protect from dark magical beasts and creatures such as the Boggart. Defence Against the Dark Arts is taught to Hogwarts students from the first year to the fifth, with the option of N.E.W.T. classes in the sixth and Seventh years for students who qualify.
Tom Riddle twice applied for the Defence Against the Dark Arts position, the first time shortly after graduation from Hogwarts. He was refused both times. According to Albus Dumbledore, after the second refusal, no Defence Against the Dark Arts teacher held the post for more than one school year. Dumbledore believed that this was due to Voldemort placing a curse on the position