A picture book combines visual and verbal narratives in a book format, most often aimed at young children. With the narrative told primarily through text, they are distinct from comics, which do so primarily through sequential images.

The images in picture books are commonly produced in a range of media, such as oil paints, acrylics, watercolor, and pencil, among others. The 'Caldecott Medal' (established 1938) and 'Kate Greenaway Medal' (established 1955) are awarded annually for illustrations in children's literature.

'Orbis Pictus' from 1658 by John Amos Comenius was the earliest illustrated book specifically for children. It is something of a children's encyclopedia and is illustrated by woodcuts. Comenius introduced a number of educational concepts and innovations including pictorial textbooks written in native languages instead of Latin.

His teaching was based in gradual development from simple to more comprehensive concepts, lifelong learning with a focus on logical thinking over dull memorization, equal opportunity for impoverished children, education for women, and universal and practical instruction.

The Comenius Medal, a United Nations Educational, Scientific and Cultural Organization (UNESCO) award honouring outstanding achievements in the fields of education research and innovation, commemorates Comenius. Comenius as been posthumously named the inventor of textbooks and primers.

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