To understand and master paper conservation, one must understand the composition and manufacturing of paper.

The composition of paper and raw material in its making has varied since its invention in 105 AD in China. The timeline of paper manufacturing technique and composition as understood from various sources is as follows:

• The invention of paper by T’sai Lun, a member of Imperial Guard and Privy Councillor, was announced to the Hai Emperor of China in A.D. 105. It was a unique event. At that time, the Chinese macerated fibers from the rice stalks, flax, hemp, and bark in water and drained the suspension on a mold covered with silk cloth. The fiber mats were removed and dried in the Sun to form paper.
• It took 500 years to reach Korea and Japan, six hundred years to Samarkand and Arab world; and 1000 years to Europe and even later to America in 1690. During this period, rags of cotton, flax, jute and hemp comprised the sole source of raw materials used in paper manufacture.
• It has been conjectured that the first paper mill was established in Baghdad
  Paper making then spread to Damascus and to Egypt and Morocco. It took 500 years to find its way to Europe.
• The Muslim conquest of Spain brought paper making into Europe.
• In Italy the first great center of the paper-making industry was Fabriano in the marquisate of Ancona. Mills were established in 1276, and rose to importance with the decline of the manufacture in Spain.
• The demand for paper was slight in the 1st Century Europe (Hunter 1943, 153) . Paper cost more than vellum, it was more fragile than parchment and it was associated with Jews and Arabs who were not trusted.
  
• It was only with the advent of printing in the middle of the 15th Century that the demand became greater.
  
• Paper has only been made from wood pulp since the 1850s.
  • Before the mid-19th century, western paper was made from cotton and linen clothing rags and by a process that largely preserved the long fibers of the raw material. While fibers may shorten with age, rag papers tend to remain strong and durable, especially if they have been stored properly in conditions not overly warm or humid.
  • Starting in the mid-19th century, wood replaced rags as the raw material for paper manufacture. Wood is processed into paper by mechanical or chemical pulping, which produces paper with shorter (compared with rag paper) fibers.
  • Mechanical pulping produces paper with the shortest fiber length and does not remove lignin from the wood, which promotes acid hydrolysis. Newspapers are printed on mechnically pulped paper. Chemical pulping removes lignin and does not cut up the cellulose chains as thoroughly as mechanical pulping, yielding a comparatively stronger paper, but which is still not as durable as rag paper.
    (https://www.loc.gov/preservation/care/deterioratebrochure.html)