Random or felted sheet of isolated vegetable fibre produced by sieving the macerated vegetable fibre from a watery slurry. Certain criteria must be met for a substance to be called paper: most importantly, the fibre must be vegetable; it must be processed in some way to break the material into individual fibres; and the sheets must be formed by casting the macerated fibre–water mixture on a sieve, usually a screen that is dipped into the aqueous mixture and allows the excess water to drain away. Paper is the most common support for Drawing, Printing, Prints, Watercolour painting and writing (see Script); with parchment, it was also widely used for the medieval Manuscript, and for the development, from the 15th century onwards, of the printed Book. For other uses, see §V 3. below; see also Conservation of paper, Banknote, Collage, Paper, decorative, Papercut, Papier mâché, Silhouette and Wallpaper; for tracing paper ...