The earliest books in the world appeared in Shang Dynasty in China, about 3000 ~4000 years ago, made of bamboo and wood. Bamboo and wood are common and easy to get. Before papermaking and printing were invented, people cut bamboo and wood into long and narrow pieces and wrote on them with a brush. Pieces cut with bamboo are called "bamboo slips", and pieces cut with wood are called "wooden slips", collectively called "bamboo slips". Jane usually only writes one line. If she makes a mistake, she will scrape it off with a knife and rewrite it. Therefore, in ancient times, she called the deleted articles "deletion", which has been used ever since. Nowadays, there are large and small book formats, and ancient bamboo slips are also long and short. The longest is three feet, and the shortest is only five inches. It takes a lot of Jane to write a book, and connecting these Jane books together becomes a "book". Hemp rope is mostly used to weave books, and silk rope (called "silk weaving") or pimp (called "Wei weaving") is also used. Bian Wei's Three Musts mentioned in ancient books refer to Confucius, a famous thinker. Because he often reads the Book of Changes, his sword has been worn out for three times. According to the length of Jane's letters, how many books should be compiled? Generally, two or three books should be compiled, and many books should be compiled four or five. Now, the word "book" representing the number of books is a hieroglyph, much like the way a rope connects simplified Chinese versions.