  paper-making is the process of making paper, a substance which is used universally today for writing and packaging. in paper-making, a dilute suspension of fibres in water is drained through a screen, so that a mat of randomly interwoven fibres is laid down. water is removed from this mat of fibres by pressing and drying to make paper. since the invention of the fourdrinier machine in the 19th century, most paper has been made from wood pulp because of cost. but other fibre sources such as cotton and textiles are used for high-quality papers. one common measure of a paper's quality is its non-wood-pulp content, e.g., 25% cotton, 50% rag, etc. previously, paper was made up of rags and hemp as well as other materials. ==history==  thumb|hemp wrapping paper, china, circa 100 bce. paper-making is known to have been traced back to china about 105 ce, when cai lun, an official attached to the imperial court during the han dynasty (202 bce-220 ce), created a sheet of paper using mulberry and other bast fibres along with fishnets, old rags, and hemp waste.papermaking. (2007). in: encyclopÃ¦dia britannica. retrieved april 9, 2007, from encyclopÃ¦dia britannica online. however a recent archaeological discovery has been reported from gansu province of paper with legible chinese writings on it dating from 8 bce,world archaeological congress enewsletter 11 august 2006 while paper had been used in china for wrapping and padding since the 2nd century bce.needham, joseph (1986). science and civilization in china: volume 5, part 1. taipei: caves books, ltd. volume 5, 122. paper used as a writing medium became widespread by the 3rd centuryneedham, volume 5, 1. and, by the 6th century, toilet paper was starting to be used in china as well.needham, volume 5, 123. during the tang dynasty (618-907 ce) paper was folded and sewn into square bags to preserve the flavour of tea, while the later song dynasty (960-1279 ce) was the first government on earth to issue paper-printed money. in the 8th century, paper spread to the islamic world, where the rudimentary and laborious process of paper-making was refined and machinery was designed for bulk manufacturing of paper. production began in baghdad where, under the supervision of the grand vizier ja'far ibn yahya, they invented a method to make a thicker sheet of paper. this helped transform paper-making from an art into a major industry.{{cite journal|first=farid|last=mahdavi|title=review: paper before print: the history and impact of paper in the
Book_arts Chinese_inventions Papermaking