Hermione Jean Granger (/hɜːrˈmaɪ. əni/ /ˈɡreɪndʒər/) is a fictional character in J. K. Rowling's Harry Potter series. She first appears in Harry Potter and the Philosopher's Stone, as a new student on her way to Hogwarts. After Harry and Ron save her from a mountain troll in the girls' restroom, she becomes best friends with them and often uses her quick wit, deft recall, and encyclopaedic knowledge to lend aid in dire situations. Rowling has stated that Hermione resembles herself as a young girl, with her insecurity and fear of failure.