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Children's literature as such probably started in the 17th century; it is generally believed that before then books were written mainly for adults.... Additionally, most printed works were hard to come by due to their cost and were mostly available for purchase only by upper class society. Scholarship on children's literature includes professional organizations, dedicated publications and university courses. There is some debate on what constitutes children's literature. The United Nations Convention on the Rights of the Child defines a child as "a human being below the age of 18 years unless under the law applicable to the child, majority is attained earlier". Some books written for children, such as The Young Visiters by Daisy Ashford or the juvenilia of Jane Austen, written to amuse brothers and sisters, are also written by children. Anne Frank wrote a novel and many very short stories in addition to her diary . Barbara Newhall Follett wrote four books, beginning with a novel called The House Without Windows at the age of nine; when the manuscript was destroyed in a fire, she rewrote it from memory.
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Young-adult fiction or young adult literature , also juvenile fiction, is fiction written, published, or marketed to adolescents and young adults.... The Young Adult Library Services of the American Library Association defines a young adult as someone between the ages of twelve and eighteen. Authors and readers of young adult novels often define the genre as literature as traditionally written for ages ranging from twelve years up to the age of eighteen, while some publishers may market young adult literature to as low as age ten or as high as age twenty-five. The terms young-adult novel, juvenile novel, young-adult book, etc. refer to the works in the YA category. YA literature shares the following fundamental elements of the fiction genre: character, plot, setting, theme, and style. However, theme and style are often subordinated to the more tangible elements of plot, setting, and character, which appeal more readily to younger readers. The vast majority of YA stories portray an adolescent, rather than an adult or child, as the protagonist.
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