Although the character of Hedwig is female, she is played on film by male owls (female snowy owls have dark patches of plumage, while only the males are completely white). The John Williams composition which serves as title music for the entire film series is named "Hedwig's Theme".

Hedwig is Harry Potter's owl, given to him in Harry Potter and the Philosopher's Stone as an eleventh birthday present by Rubeus Hagrid, who purchases the owl in Diagon Alley at the Eeylops Owl Emporium. Harry gives her this name after reading it in a book on the history of magic. Hedwig is used for delivering messages throughout the series, and also serves as a companion to Harry, especially when he is unable to interact with other wizards. It is implied throughout the books that Hedwig can fully understand Harry's speech. In the fifth book, Order of the Phoenix, Hedwig is intercepted by Dolores Umbridge and is hurt, but is later healed by Professor Grubbly-Plank. In the seventh book, The Deathly Hallows, Hedwig is killed by a curse from a Death Eater; in the film version, she is killed defending Harry from the Death Eater. According to Rowling, Hedwig's death represents the loss of Harry's innocence.

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