1. Book block: the unused book must reach a certain thickness.
2. Used books: regardless of the degree of use.
3. Kraft paper: generally used for packaging.
4. Book core: For new books, remove the cover and the remaining paper from the adhesive (non-coated paper, white paper and black letters, no color).
5. White paper: pure white, no film.
6. Binding paper edge: the paper edge cut off when printing a book, with words.
7. Yellow cardboard: discarded packaging boxes, mainly yellow.
8. Gray card: gray from the outside to the core, with colors available.
9. New newspaper: a newspaper that has not been used.
10. Old newspapers: generally come from used newspapers from waste paper purchase stations.
11. Newspaper: Same quality as newspaper paper, without color words.
12. Coated paper: The paper used for most book covers has no film and has a certain color.
13. Cup paper: paper left over from the production of paper cups (generally paper bowls also belong to this category).
14. Tetra Pak packaging: such as paper milk cartons.
15. Book pages: relatively messy paper, no film, but text. (Non-coated paper)