Newt Scamander is credited as the fictional author of Fantastic Beasts and Where to Find Them.
The book first appeared in the Harry Potter world as a Hogwarts textbook. Its fictional author, Newton Artemis Fido Scamander, is a magizoologist who studies magical creatures. The published companion book was presented as Harry’s school copy, complete with humorous notes attributed to Harry and Ron.
Rowling later developed Newt into the central character of the Fantastic Beasts film series. In those films, he is portrayed as a British wizard whose work with magical creatures takes him across the world, including to New York in 1926.
Newt is distinct from Hagrid, who teaches Care of Magical Creatures at Hogwarts for part of the original series. The fictional textbook and the later screenplay-based films share the character but are different works in the wider Wizarding World.