Children's literature is defined as literature directed toward the child reader, plus the set of literary texts that society has deemed suitable for children, but they were written originally thinking of adult readers (eg Gulliver's Travels, The Island Treasure or Platero and I).

In another sense of the term, less common, also includes literary pieces written by children themselves. On the other hand, sometimes it is considered that the concept includes juvenile literature, written for or by teens, but what is more correct to call the whole children's literature or abbreviated LIJ.

The modern literary criticism considered essential nature of "literature" in this kind of writing, so that today it is excluded from the current production of essentially moral or educational texts, while still giving priority to these concepts throughout the LIJ given the context education which develops their reading. This is a very new concept and almost unprecedented in the history of literature.

Literature for children has grown from a largely unknown in the publishing world to grab the attention of the world of books, which is enormous production, the increasing number of literary awards LIJ and the volume of profits it generates. This is due in large part to the settlement of the conception of childhood as a stage of human development itself and specific, that is, the idea that children are not and small adults, or adults with disabilities, has been extended in most societies, so the need to develop a literature and legibly addressed to and by the public is growing.

The conception of infancy or childhood, does not emerge in societies until the advent of the modern age and not widespread until the late nineteenth century. In the Middle Ages there was no notion of childhood as a distinct period and in need of specific works, so there is not exactly a children's literature. That does not mean that children had no literary experience, but is not defined in terms distinct from the adult experience. Since hoarding of knowledge and culture by clergy and other estates, the few works read by the people wanted to instill values and teach dogma, so the figure of the book as a teaching vehicle is present throughout the Middle Ages and of the Renaissance. Among the books read by children of that age can find the bestiary, alphabets or primers. This could include some of these classical works, like Aesop's fables in which, to be personified animals, were geared to this audience.

Where the seventeenth century, the landscape begins to change and are increasingly dealing fantasy works, being a true reflection of the myths, legends and stories, typical of oral transmission, which has been gathering knowledge of popular culture through the narration of these, by the older generations to generations of children. In addition to writing these works or stories, which include authors such as Charles Perrault and Madame Leprince de Beaumont, stands the figure of the fabulist, Felix Maria Iriarte Samaniegoo Thomas. At this time, moreover, two events occur significance for what is now known as Children's Literature, publication, first of Gulliver's Travels-Jonathan Swift-and, second, Robinson Crusoe-Daniel Defoe-clear examples of what remains today are two issues that meets the LIJ: tales of adventure and enter imagined worlds, uncharted and different.

Once at the nineteenth century with the Romantic movement up the golden age of children's literature. Many authors who publish their works with an extraordinary acceptance among the younger audience. These are the tales (Hans Christian Andersen, Countess de Segur, Wilhelm and Jacob Grimm and Oscar Wilde in Europe, and Saturnino Calleja and Fernan Caballero in Spain) and novels like Alice in Wonderland-Lewis Carroll-Island Robert L. Treasure Stevenson, The Jungle Book by Rudyard Kipling, Pinoccio-Carlo Collodi, "those written by Jules Verne or The Adventures of Tom Sawyer among others, which led to a novel context for the establishment of a new literary genre for the reader more young in the twentieth century, where the massive production of LIJ coexists with the works of the adult genre.

There are many famous works of the LIJ quote, as is the case of Peter Pan, The Little Prince, The Wind in the Willows, Pippi Longstocking or collection of stories about the Moomin family, in all of them highlights a new vision to offer to young readers, where in addition to addressing issues such classics as the adventures or discovery of new worlds, seek to overcome the fear, freedom, aspirations, the world of dreams and desires, as acts of rebellion against the adult world. This production is greatly increased in the 70's, 80 and 90, with authors such as Roald Dahl, Gianni Rodari, Michael Ende, René Goscinny (Little Nicholas), (Christine Nöstlinger, Laura Gallego Garcia and Henriette Bichonnier among others. In this twentieth century, in addition, new formats LIJ through painting techniques and illustrating stories, where words are accompanied by images that contextualize the story and providing connecting links to history, is the appearance in the book-album or picture book, a genre in which authors such as Maurice Sendak stand, Janosch, Quentin Blake, Leo Lionni, Babette Cole, Ulises Wensell or Fernando Puig Rosado.

Already, in the XXI century, the LIJ is well established in Western countries, where sales are huge and vast literary production.