The abbreviation stands for the American Backgammon Tour. The American Backgammon Tour is a backgammon competition in which the participants of the major competitions from the United States of America get master points. The event is held annually, and the points are given as following: only the tournament money winners are given master points. There are three divisions: the highest division (Championship, Open Championship) or A division: the winner will be assigned 1 point. The second division (Advanced, Intermediate) or B division the winner will be assigned 0.5 point and in the lower divisions (Low Intermediate, Limited, Beginner, Novice) or the C division the winner is assigned 0.25 points.