Professor Albus Percival Wulfric Brian Dumbledore is a fictional character in J. K. Rowling's Harry Potter series. For most of the series, he is the headmaster of the wizarding school Hogwarts. As part of his backstory, it is revealed that he is the founder and leader of the Order of the Phoenix, an organisation dedicated to fighting Lord Voldemort.
Dumbledore is portrayed by Richard Harris in the film adaptations of Harry Potter and the Philosopher's Stone and Harry Potter and the Chamber of Secrets. After Harris' death, Michael Gambon portrayed Dumbledore for all of the remaining films.
Rowling stated she chose the name Dumbledore, which is an Early Modern English word for "bumblebee", because of Dumbledore's love of music: she imagined him walking around "humming to himself a lot". More: en.wikipedia.org.