Defence Against the Dark Arts is a subject taught at Hogwarts School of Witchcraft and Wizardry in the Harry Potter series. The course focuses on teaching students how to protect themselves from dark magic, including curses, hexes, and other malevolent forces. Each year, students learn different techniques and spells to defend against various threats. The subject has a troubled history, with a new teacher assigned each year, often due to the challenges posed by dark forces. Notable instructors include Remus Lupin, Dolores Umbridge, and Severus Snape, each bringing their unique approach to the curriculum.