Tong (tóng) is a Chinese character and its pinyin is tóng. It consists of "water" and "east", indicating the way water flows eastward. The origin of Tongzi can be traced back to the Han Dynasty, and it was first seen in Historical Records, Mencius and Biography of Xun Qing: "There are five emperors in the sky, five kings in the earth, and rivers, Huai, Tong, Wei, Sha and Jing in the water." As a place name, Tongguan was often called Tongguan in ancient times (now northwest of Xi City, Shaanxi Province) because it is located on the south bank of the Yellow River, an important gateway connecting Guanzhong and northwest, and an important military fortress for Emperor Wu of Han Dynasty to consolidate his rule in Guanzhong. At the same time, Tongguan is also an important pass on the Silk Road and was once one of the distribution centers of Chinese and foreign trade.
Later, Tong was not only used as a place name, but also used to name people and articles. For example, Bai Juyi, a poet in the Tang Dynasty, wrote a poem: "In February, Tongguan Road was covered with snow." Tongguan Road refers to the road leading to Tongguan. In addition, copper is also used to name items such as copper carts and copper official posts.
Generally speaking, Chinese characters have a long history and cultural heritage in the history of China. It is not only a place name, but also the name of people and things, which has contributed to the richness and diversity of China culture.