Pool games are as varied as the people who play them, and the people who play pool are a diverse group indeed. Most official billiards games are played until a player acquires 150 points, though this number can vary. Though generally only two players play at a time, "cutthroat" games featuring three players or "doubles" games are common. There are also several different ways to keep score in pool, including dials, chains, chalkboards or just good old-fashioned pen and paper. "Straight pool" or 14.1 is the most common pool game, but 9-Ball and 8-Ball are popular as well. Regardless of all these variants, the scoring of all pool games is basically the same.
Determine the total number of points that will be played, the type of game you will play and which scoring mechanism will be used.
Assign each player two columns or scoring mechanisms, one for match score and one for total score. The match score---as its name implies---is a player's score at the end of a match. The total score is the cumulative total of a player's match score for all the matches played in the game.
Play the pool match in accordance with the standard rules of the game you have chosen. For a complete reference of the rules of various billiards games, see Resources.
Assign one point to a player's match score for every ball that she legally pockets. A player's turn is over when he fails to legally pocket a ball, or when all balls have been pocketed.
Subtract two points from a player's total score for a breaking foul, which occurs when a player fails to hit either of the two corner balls or the 8 ball into a pocket or against a bank. Subtract one point from a player's score for scratching. Depending on the game, scratching can include all or some of the following: pocketing the cue ball (when either shooting at only the 8 ball or any ball), pocketing any ball in a pocket you did not intend, pocketing only the 8 ball in a pocket you did not intend or pocketing any ball out of order. See Resources for a complete reference of types of games.
Add the match score of each player to his respective total score when all balls have been pocketed or the balls must be reracked. The match-points total then returns to "0" for all players for the next match.
End the game when one player's total score has reached the assigned number of points.
Another way to assign points is to coordinate the point value for each ball with the number on that particular ball. For instance if you pocket the 8 Ball, you receive eight points toward your match score.