How is 9 balls pool played?

OBJECT OF THE GAME. Nine Ball is played with nine object balls numbered one through nine and a cue ball. On each shot the first ball the cue ball contacts must be the lowest-numbered ball on the table, but the balls need not be pocketed in order. If a player pockets any ball on a legal shot, he remains at the table for another shot, and continues until he misses, fouls, or wins the game by pocketing the 9-ball. After a miss, the incoming player must shoot from the position left by the previous player, but after any foul the incoming player may place the cue ball anywhere on the table. Players are not required to call any shot.