Children's literature or juvenile literature includes stories, books, magazines, and poems that are created for children. Modern children's literature is classified in two different ways: genre or the intended age of the reader, from picture books for the very young to young adult fiction.
Children's literature can be traced to traditional stories like fairy tales, that have only been identified as children's literature in the eighteenth century, and songs, part of a wider oral tradition, that adults shared with children before publishing existed. The development of early children's literature, before printing was invented, is difficult to trace. Even after printing became widespread, many classic "children's" tales were originally created for adults and later adapted for a younger audience. Since the fifteenth century much literature has been aimed specifically at children, often with a moral or religious message. Children's literature has been shaped by religious sources, like Puritan traditions, or by more philosophical and scientific standpoints with the influences of Charles Darwin and John Locke. The late nineteenth and early twentieth centuries are known as the "Golden Age of Children's Literature" because many classic children's books were published then.
There is no single or widely used definition of children's literature. It can be broadly defined as the body of written works and accompanying illustrations produced in order to entertain or instruct young people. The genre encompasses a wide range of works, including acknowledged classics of world literature, picture books and easy-to-read stories written exclusively for children, and fairy tales, lullabies, fables, folk songs, and other primarily orally transmitted materials or more specifically defined as fiction, non-fiction, poetry, or drama intended for and used by children and young people. One writer on children's literature defines it as "all books written for children, excluding works such as comic books, joke books, cartoon books, and non-fiction works that are not intended to be read from front to back, such as dictionaries, encyclopedias, and other reference materials".