Small seal script, or xiaozhuang characters, was the first set of Chinese characters that were made the standard all across China. Previously, each of the Warring States had their own Chinese characters. People from one state did not understand the characters from another. When the Qin dynasty (221 BC to 206 BC) conquered the other states, Emperor Qin Shi Huang forced all Imperial China to use Qin characters and Qin units of measurement. This allowed people all across China to communicate with each other without confusion.