Prior to the invention of paper during later stage of Han Dynasty, for a long time Chinese people had use chisels (or knives) as "writing" tool to inscribe words on bamboo slips, so as to preserve their great cultural heritage.  (Certainly, ancient people could use brushes to write with on silks, but that would be too expensive.)  I believe most of modern Chineses have not seen those bamboo slips until 1950s. 

A great deal of bamboo slips were unearthed in Province of Hunan after New China was founded, and a large part of them were found in Changsha.  Through textual research, experts concluded most of those bamboo slips were pertaining to that of Wu in the era of Three Kingdoms.  Now all of them are well-preserved and exhibited in the Museum of Bamboo Slip at Changsha. 

A scholarly, professional, but aged interpreter led us to "The Road to Civilization": the brief introduction on the production process of bamboo slips,  the ones of Wu in Three Kingdoms, the history of Chinese bamboo slips,  different language carriers of the world,  and Chinese bamboo slips calligraphy.  The interpretation was so vivid that all of the audience gave him a big round of applause when he finished his touring.  FYI, our tour guide told us some of the interpreters of the museum are retired professors who are volunteering the services.  I guess most likely the interpreter serving us must be one among them.  

P.S.  You may ask since paper was already invented in Han Dynasty, why did people in later time of Three Kingdoms were still using bamboo slips to write with.  Well, I think in the incipient stage paper had not so widely disseminated that were available to public.  After all, it was not until Song Dynasty, almost a thousand years had passed since the usage of paper, did emerge an advanced typography in China.