The Hogwarts library contains tens of thousands of books on thousands of shelves. Included in its many sections is an Invisibility Section, a section with information about dragons, and a Restricted Section at the back, set off with a rope. A signed note from a teacher is required to peruse that section of the library; it contains books of Dark Magic only used by older students studying advanced Defence Against the Dark Arts. One of the books in this section screams when opened.
The library books have various spells on them to prevent students from defacing or stealing them. Chocolate (and presumably other food) is forbidden in the library.
The library closes at 8 pm.
