American mahjong
The winds
東南西北: the four wind tiles, the seats at the table they name, and the letters American sets add.
What it means
東南西北: dōng, nán, xī, běi; east, south, west, north. The four winds are the four seats at the table, and the game moves round them in that order, which is the order a Chinese compass reads, not the one an English one does.
American sets add the letter E, S, W or N above the character so a reader of either script finds the tile. Here the character and the letter are both part of the information layer; a set may color them and may not change them.
The dealer sits in the east, and the hand number counts the deal round the table.
The tiles, one by one
Screen 5 of 9 in What's on the tile.
A historian's review of the history on these screens is pending.