1. Infant literature: targeted at infants aged to 6, the content is simple nursery rhymes, fairy tales, picture books, etc.
2. Children's literature: Children aged 7 to 12 are targeted at readers, and the contents are children's stories, fairy tales, children's novels, children's poems, etc.
3. Juvenile literature: targeted at teenagers aged 13 to 18, the content is juvenile novels, juvenile poems, juvenile essays, etc.