Which 2001 J.K. Rowling book was a companion volume to the Hogwarts library?

Fantastic Beasts and Where to Find Them was a 2001 J.K. Rowling companion book presented as part of the Hogwarts library.

The book is framed as a textbook written by Newt Scamander, a fictional magizoologist. Harry, Ron, and Hermione are depicted as owning a Hogwarts library copy, and the edition includes humorous notes attributed to Harry and Ron. The text lists magical creatures and gives brief descriptions of them.

Rowling wrote the book to support Comic Relief, with proceeds from the original publication helping charitable work. It was released alongside Quidditch Through the Ages, another short companion volume credited within the wizarding world to Kennilworthy Whisp.

The title later became the basis for a film series. Rowling wrote the screenplay for Fantastic Beasts and Where to Find Them, released in 2016. The textbook and the film are related through their fictional author and setting, but they are not the same story.