Pollyanna is a 1913 novel by American author Eleanor H. Porter, considered a classic of children's literature. The book's success led to Porter's soon writing a sequel, Pollyanna Grows Up (1915). Eleven more Pollyanna sequels, known as "Glad Books", were later published, most of them written by Elizabeth Borton or Harriet Lummis Smith. Further sequels followed, including Pollyanna Plays the Game by Colleen L. Reece, published in 1997. Due to the book's fame.

The title character is Pollyanna Whittier, an eleven-year-old orphan who goes to live in the fictional town of Beldingsville, Vermont, with her wealthy but stern and cold spinster Aunt Polly Harrington, who does not want to take in Pollyanna but feels it is her duty to her late sister Jennifer. Pollyanna's philosophy of life centers on what she calls "The Glad Game", an optimistic and positive attitude she learned from her father. The game consists of finding something to be glad about in every situation, no matter how bleak it may be. It originated in an incident one Christmas when Pollyanna, who was hoping for a doll in the missionary barrel, found only a pair of crutches inside. Making the game up on the spot, Pollyanna's father taught her to look at the good side of things—in this case, to be glad about the crutches because she did not need to use them.