Imperial Outline refers to the gifts or tributes given to the emperor by courtiers or vassals in ancient China.
Huanggang is a general term, which refers to all the items contained in this behavior, and refers to the physical objects.
Another meaning of imperial procedure refers to the laws and systems formulated by the imperial court represented by the emperor, which are intangible.
Robbery of the emperor refers to the items robbed by fugitives from the emperor in the past, usually a large number of gold, silver, jewelry, jade and antiques.
At the end of Sui Dynasty, Cheng once robbed Huanggang. In addition, a similar plot happened in Water Margin.
There is a story of "outwitting the birth class" in the Water Margin.
Birthday category refers to birthday gifts sent in batches.
Class refers to the organization that transports goods in batches, such as tea class, salt class and flower stone class. The second definition of "outline" in Dictionary of Common Words in Ancient Chinese: the organization of transporting goods in batches in Tang and Song Dynasties. Such as salt, tea and flower stone.