What did the ancients call letters?

In ancient China, letters were different. Books refer to letters, believers. Later, letters were generally called letters. In other words, modern letters were usually called "books" in ancient times. "Zuo Zhuan" records: "The uncle made the son produce books." Famous letters, such as Sima Qian's Letter to Ren An. In modern Chinese, "book" still retains the meaning of "letter", such as "letter from home". The nicknames of ancient books are introduced as follows: Hongyan: It is said that Hongyan can pass books in ancient times. This allusion comes from Hanshu? 6? 1 Su Wu Biography: "It is said that the son of heaven shot Lin Deyan and wrote martial arts on silk in a river." So, later, red rocks were used instead of letters. Carp: This allusion comes from the poem "Drinking Horses in the Great Wall Grottoes" written by Han Yuefu: "The guest came from afar, left me a pair of carp, and called for cooking carp, and there were books in it." There are several ways to replace letters with carp, including "Pisces", "Double Carp" and "Fish Book". In addition, ancient people often made letters into the shape of carp. Credo: Credo originally refers to the mailbox of letters. After ancient letters are written, they are usually found in a bamboo tube or wooden tube and then sent out. Later, the book tube also became synonymous with letters. Eight-part essay: In the old days, letters had eight lines per page, so it was called eight-part essay. Jane: Before papermaking was invented, long and narrow bamboo pieces were used as writing materials in China. People call this kind of bamboo chip Jane. The bamboo pieces used to write letters are called bamboo slips. Xie: The thin and small wood used for writing in ancient times was called Xie. Bamboo slips and Xie Chuan were written together in the Han Dynasty, and the imperial edict was no more than three feet wide, while ordinary letters were only one foot wide, so this kind of letter was called a letter. Cambodia: Cambodia and bamboo slips were commonly used in ancient times, which were letters, business cards and posts, such as invitations, congratulatory letters and books. Sue: In ancient times, white silk was called Sue. Letters written in white silk (or silk) are called geometry, and later "geometry" became synonymous with letters. Writing paper: Writing paper was originally a beautiful bamboo for people to write poems or paintings. General stationery is also called stationery, and later it is synonymous with letters. Letter: The original letter refers to the envelope of the letter. In ancient times, letters were sent in wooden boxes, which was called letters. Later, letters were called letters, such as letters, letters and official letters. Zagreb: Zagreb refers to ancient letters and public and private documents. Zagreb originally meant small wooden slips used for ancient writing. The word "letter" is still widely used.