In Japan the points (other then center) are show the place for handicup stones.
In ancient Japan during playing Ninuki (Pente) more stronger player gave handicup.
If you win three games in a Row , then you have play with this player only as second.
If then you also win three games in a row , he get possibility to put one more additional stone at the board but only in points specially marked at the board.
And so on till 4-5 stones handicup.
Each stone of handicup means the rank difference.
Alexander