What was the tributary trade system in Ming Dynasty?

Tribute trade is tribute trade, and neighboring countries pay tribute to Ming Chengzu, and Ming Chengzu returns. This tribute relationship was not initiated by the Ming Dynasty and existed since ancient times, but it became the main form of foreign trade in the Ming Dynasty because of the closed-door policy of the Ming Dynasty. In order to maintain trade relations with China, neighboring countries have adopted this method. In order to maintain the face of "going to the country", Ming Chengzu often paid tribute, so neighboring countries enjoyed it.