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. J. K Rowling has stated that Hermione resembles herself as a young girl, with her insecurity and fear of failure.