What do windows, mirrors, and sliding glass door have to do with reading? This phrase was first coined in 1990 by Dr. Rudine Sims Bishop to explain how children learn about themselves and those around them through literature. Books that act as windows give children (and adults) a view into a world that is different from their own. Here the reader can learn about different cultures and experiences outside of their normal everyday life. Books that act as sliding glass doors work similar to windows but allow the reader to be fully immersed in a book, using their imagination to travel back and forth between the two worlds. Books that act as mirrors are reflections of the reader. When readers see themselves in books, they feel valued and understood.