Dame are neutral points in yose, the endgame. Placing a stone on such a point won't gain either side any points. In some sets of rules however, most notably the Chinese, every stone placed on the board is worth a point. The question of whether a point is dame then becomes a question of whether the number of dame points left is even or odd. In the latter case, being the first to start playing dame is worth one point; regardless of the how many are to play (as long as their number is odd).