"Zi" is a spell of many tribes in ancient times, which appeared in the history of ancient India, Persia, Greece, Egypt, Troy and other countries, and was later used by some ancient religions. At first, people regarded it as a symbol of the sun or fire, and later it was generally regarded as an auspicious symbol. With the spread of ancient Indian Buddhism, the word "Zi" was also introduced to China. This word was read in Sanskrit.