A picture book combines visual and verbal narratives in a book format, most often aimed at young children. The images in picture books use a range of media such as oil paints, acrylics, watercolor, and pencil, among others. Two of the earliest books with something like the format picture books still retain now were Heinrich Hoffmann's Struwwelpeter from 1845 and Beatrix Potter's The Tale of Peter Rabbit from 1902. Some of the best-known picture books are Robert McCloskey's Make Way for Ducklings, Dr. Seuss' The Cat In The Hat, and Maurice Sendak's Where the Wild Things Are. The Caldecott Medal (established 1938) and Kate Greenaway Medal (established 1955) are awarded annually for illustrations in children's literature. From the mid-1960s several children's literature awards include a category for picture books.Target audiencesPicture books are most often aimed at young children, and while some may have very basic language especially designed to help children develop their reading skills, most are written with vocabulary a child can understand but not necessarily read. For this reason, picture books tend to have two functions in the lives of children: they are first read to young children by adults, and then children read them themselves once they begin learning to read.