The program allows you to play in rating mode or non-rating mode. This option lets you decide that. For non-rating mode, the profiles of players are not changed when the game is over. For rating mode, winner gains points and loser loses points. The exact points won or lost are computed using a pretty complicated formula to ensure fairness. You gain more points if you win good players, and lose less points if you lose to them. No points gained/lost if the game is drawn. The points gained/lost by the two players in a game are normally the same. For new player (username ends with N) and for provisional player (profile end with P), the points gained/lost will be a factor of 1, 2, 4, or 8 times more than his/her opponent. This is needed so that new player quickly achieves the score suitable with his/her the level. New players are those with less than 10 winning or losing games. Provisional players are those with 10 to 19 winning or losing games.