Expelliarmus spellbook

"However, I do remember reading somewhere that the Alohomore spellbook is kept in the library - I've heard there's a shortcut to the library down THAT corridor."

- Hermione Granger says to Harry Potter where is located the spellbook.

The Expelliarmus spellbook is a book that contained information on the Disarming Charm. It also contained the instructions on how to perform the spell.

During his second year, Harry Potter was chosen by Gilderoy Lockhart, to try the spell's challenge, and to retrieve this spellbook. Harry succeeded and effectively learnt the Disarming Charm. During his third year, Harry and Ron Weasley decided to show the Folio Bruti to Hermione Granger, in the Gryffindor common room. But, Hermione learned Harry and Ron were had some problems with Draco Malfoy, in the Hogwarts Express. She said they could use the Disarming Charm and she showed them the spellbook. Then, Harry and Ron learnt the spell.

Appearances

 * Harry Potter and the Chamber of Secrets (video game)
 * Harry Potter and the Prisoner of Azkaban (video game)