Hogwarts song, each student in turn is seated upon the stool in front of the rest of the student body. The Hat is placed on the student's head, whereupon it examines his or her mind and assigns them to one of the four Houses based on abilities, personality, and preferences. After the Sorting Ceremony, the students and teachers enjoy a feast, prepared by the Hogwarts house-elves. If Dumbledore is feeling cheerful, he will lead the students in singing the school song. Hogwarts is divided into four houses, each bearing the last name of its founder: Godric Gryffindor, Salazar Slytherin, Rowena Ravenclaw
Hogwarts staff However, in the American edition of "Half-Blood Prince", it is re-spelled as "Sybill", matching the UK edition. Professor Trelawney is portrayed by Emma Thompson in the "Prisoner of Azkaban", "Order of the Phoenix", and "Deathly Hallows Part 2". Hogwarts houses at least twenty ghosts, but when people in the novels speak of the ghosts at Hogwarts they usually refer to one of the four resident ghosts of the Hogwarts houses: Sir Nicholas de Mimsy-Porpington (or, as the students refer to him, Nearly Headless Nick), the almost beheaded ghost of Gryffindor house; the Bloody Baron, who is the ghost of Slytherin