Joanne Rowling , (/ˈroʊlɪŋ/ "rolling"; born 31 July 1965), writing under the pen names J. K. Rowling and Robert Galbraith, is a Britishwriter. She wrote the Harry Potter books. She only uses the name J. K. Rowling for her books: the "K" stands for "Kathleen", which was the first name of her grandmother.