A seal can also be defined as a stamp. Both the Chinese official and private seal of various dynasties have different titles, such as stamp, zhu not, contract, fu, lease and others. The seals used by the emperors of ancient China were called xi, yin, bao, etc..
According to historical records, seals were widely used during the Warring States period (475 BC ---221 BC). The making of a seal is to engrave fonts, such as seal characters and official script and so on; or images in the form of intaglio and embossment into the seal, basically shaped as round or square. Covered with a vermilion overlay, the Chinese seal is not only used in daily life, but it is also used to represent signatures on paintings and calligraphies. It is gradually becoming one of China’s unique artworks.