It is said to have served both as a road sign and a place for passersby to leave messages, emerging during the Yao and Shun era of the primitive society. Back then, people would set up a wooden pillar along major thoroughfares to identify the road and act as a marker. Later, post stations and relay stations also used it for identification. It was known as "Huán Mù" or "Biao Mù," later collectively referred to as "Huán Mù" because the ancient character "Huán" sounds similar to "Hua." Over time, it was pronounced as "Hua Biao." On this wooden pillar, passersby could carve their opinions, hence it was also called "Bao Mù" or "Fei Bao Mù." The term "fei biao" in ancient times meant discussing right and wrong, akin to modern-day feedback. Therefore, it also served a function similar to today's "suggestion box." Historical records indicate that during Yao's time, the "fei biao" was made by crossing a horizontal wooden beam with the pillar.