The game of straight pool uses 15 numbered balls and a white cue ball.  The players can attempt to pocket the balls in any order they choose, however they must "call the shot" (say which pocket they are going to sink it into to) before they shoot the ball.  When they are left with only one ball on the table the 14 balls are racked and broke again while the player attempts to pocket the last remaining ball.  One point is given for every ball made prior to sinking the last ball.  The set amount of points needed to win is usually 150.