Fouls

A foul is a shot or action by the striker which is against the rules of the game. When a foul is made during a shot, the player's turn is ended and he will receive no points for the foul shot. The other player will receive penalty points.

Common fouls are:

failing to hit any other ball with the cue ball
first hitting a ball "not-on" with the cue ball
potting a ball "not-on"
potting the white (in-off)
hitting a ball other than the white with the cue
making a ball land off the table
touching the cue ball with anything other than the tip of the cue (except while positioning the cue ball "in-hand"; while "in-hand" the cue ball may be touched by anything except the tip of the cue)
playing a "push shot" - a shot where the cue ball is in simultaneous contact with the cue tip and another ball (except when playing the cue ball away from a "touching ball"; for this purpose a "touching ball" may refer to any ball, "on" or not.)
playing a "jump shot" - a shot where the cue ball leaves the bed of the table and jumps over a ball before first hitting another ball
playing a shot with both feet off the ground.

It is sometimes erroneously believed that if two balls are potted in one shot it is a foul. However, when the reds are "on", multiple reds can be potted and this is not a foul: the player scores 1 point per red.

Should a cue ball be touched with the tip while "in-hand", i.e. when breaking-off or playing from the "D" after being potted, a foul is not committed as long as the referee is satisfied that the player was only positioning the ball, and not playing, or preparing to play, a shot.

When a foul is made, the non-fouling player will receive penalty points equal to the value of the ball "on", or the value of any of the "foul" balls, or 4 points, whichever is highest. When multiple fouls are made in one shot, only the most highly valued foul is counted. Penalty points are therefore at least 4 points and at most 7.

Not hitting the ball "on" first is the most common foul. A player can make life difficult for his opponent by making sure he cannot hit a ball "on" directly. This is most commonly called "snookering" one's opponent or alternatively "laying a snooker" or putting the other player "in a snooker".

Because players receive points for fouls by their opponents, snookering one's opponent a number of times in a row is a possible way of winning a frame when potting all the balls on the table would be insufficient to ensure a win.

If a player commits a foul, and the opponent considers that the position left is unattractive, he may request that the offender play again from the resulting position.

Free ball

A free ball is a player-nominated substitute for the ball on when the player is snookered by a foul. This is because the snooker in this case is produced by a foul and thus not considered legitimate. As such the player is allowed to pick any ball as a free ball, which is then effectively treated as the ball on, thereby voiding the illegitimate snooker. Once the free ball shot is taken legally, the game continues normally (although, if the offending player was asked to play the shot again, then the free ball is void, having to resolve the self-inflicted snooker).

For example, as illustrated in the provided picture, if the ball on is the final red, but is snookered by the black due to a foul, the player will be able to name the blue as the free ball. He could then pot the blue as if it were a red for one point. The blue will then be respotted, a nominated colour ball will be on, and normal play will resume.

Note that, as a natural corollary of the rules, the free ball is always a colour ball. If the ball on is a red, then by definition it cannot be snookered via another red, as it merely provides an alternative clean shot with another ball on. If the ball on is a red, and is snookered by a colour after a foul, then logically the red is either the final one or all reds are snookered by a colour ball, meaning the free ball has to be a colour. If the ball on is a colour ball that is snookered by a red, a previous red must have been successfully potted; the snooker therefore must be self-inflicted and cannot have occurred as the result of a foul. If the ball on is a colour that is snookered by another colour after a foul, all reds must have been already potted; thus the free ball still has to be a colour ball.

Interesting situations could occur if somehow both the free ball and the real ball on are potted. If a colour was the ball on (all reds were potted), and both the free ball and the actual ball on are potted, only the ball on is scored. The free ball is respotted while the actual ball on will stay off the table. This is the only time when attempting to pot a colour that two balls can be potted without a foul occurring, because technically speaking both of the potted balls are on.

If the ball on is red and both the free ball and a real red are potted, then each ball potted is scored as a red for a total of two points. The colour free ball is then respotted and the red remains off the table. By the same logic, it is allowed to cannon a free ball onto a real red to pot the latter (a plant). Going back to the picture above, the player could nominate the black as the free ball, and proceed to plant the real red using the black free ball; if the player somehow potted them both, two points would be awarded and the black would be respotted.

Not potting the free ball incurs no penalty, so the striker may play a snooker using the free ball, gratis. However, if said snooker is achieved by having the free ball obstructing the ball on, then the strike is a foul and a penalty of the value of the ball on is awarded to the opponent. The reason is that the free ball was to be treated as the ball on, and one cannot snooker a ball on by another ball on (following the same logic that a red cannot snooker another red when red is on). The only exception to this is when there are only two balls remaining on the table, namely pink and black. If the opposition somehow fouled trying to pot pink, and illegitimately snookered the striker with the black, then it is fair for the striker to snooker the opposition "back" with the free black ball.

A free ball scenario does not occur when the ball gets stuck at the edge of a pocket jaw (commonly referred to as "angled') in such a manner that the player is unable to hit any ball on. This is because according to the official snooker rules a ball is snookered only if its way is obstructed by balls not on. In this scenario, after a foul, the player may choose to either take the shot from the current position or ask the offender to play again, as per the usual rules on fouls.

Foul and a miss

A foul and a miss will be called if a player does not hit the ball "on" first (foul) and is deemed by the referee to have not made the best possible attempt (miss). In this case, the opponent has the option to request that all balls on the table to be returned to their position before the foul, and require the fouling player to take the shot again.

The rule was introduced to prevent players from playing professional fouls (i.e., deliberately fouling so as to leave the balls in a safe position, reducing the risk of giving a frame-winning chance to the opponent). Multiple misses often occur because players attempt to hit a shot very softly or thinly in situations where a fuller contact might leave their opponent an easy potting chance. This can lead to an apparently easy escape being attempted several times, as players feel that it is better to concede many points but leave a safe position, than concede none and leave a frame-winning chance.

Note that "best attempt" here has a couple of elements. Firstly, the shot selection must be the easiest to be achieved, so deliberately taking a difficult shot to foul tactically will be still liable to be called a miss. Secondly, sufficient strength must be put into the shot such that the cue ball can even reach the ball "on" (it's possible for the referee not to call a miss if a striker would or did overshoot, but undershooting always results in a miss). Finally, the striker must try to hit the ball "on" as best as he can, getting the cue ball as near to the target as possible. All three of these elements must be present for a striker to be considered to have made a "best attempt", and not just the third element.

There are three situations where a miss will not be called even if the striker failed to do a "best attempt":

1)If either of the players is in need of penalty points to win the frame, or if either players would be in need of further penalty points to win the frame after the current penalty is applied, then a miss will never be called. This is to prevent the score difference from increasing indefinitely due to misses in worst-case scenarios.

2)If the points on the table are equal to the score difference, either before or after the penalty is applied, then a miss may not be called, should the referee believe that the foul was not on purpose. This can prevent the score difference from decreasing too much, at the discretion of the referee.

3)If it is physically impossible to play a legal shot, then it must be assumed that the striker is trying their best already, though the striker must still put sufficient strength in the stroke such that the cue ball would reach its target were it not due to the obstruction. This can happen if the cue ball was completely snookered - since jump shots are fouls in the first place, there is no other way this scenario could end.

A special case occurs after a striker fouls and misses in a non-snookered scenario -- that is, when he fails to hit a ball "on" when there is a clear path to the ball or part of the ball. Should the opposition choose to have the offender play from the position prior to the missing stroke under this situation, then a further failure to provide a best attempt will be called foul and a miss regardless of score difference. A warning is issued, and a third failure will forfeit the frame to the opposition.

Outline

SPORTS WORLD

Snooker

Snooker is a cue sport that is played on a baize-covered table with pockets in each of the four corners and in the middle of each of the long side cushions. It is played using a cue and snooker balls: one white cue ball, 15 red balls worth one point each, and six balls of different colours: yellow (2 points), green (3), brown (4), blue (5), pink (6), black (7).

History: The origin of snooker dates back to the latter half of the nineteenth century. In the 1870s, billiards was a popular activity amongst British Army officers stationed in India and several variations of the game were devised during this time.

Equipment: Snooker is played on a rectangular snooker table with six pockets, one at each corner and one in the middle of each long side. The table usually has a slate base, covered in green baize.

Gameplay: At the beginning of each frame the balls are set up by the referee. This will be followed by a break-off shot, on which the players take turns.

Fouls: A foul is a shot or action by the striker which is against the rules of the game. When a foul is made during a shot, the player's turn is ended and he will receive no points for the foul shot.

End of a frame: When the black is the only object ball remaining, and the striker leads by more than seven points, the striker may claim the win, but may also elect to proceed with potting the black, for example to complete a high-scoring break.

SPORTS

Snooker

Snooker is a cue sport that is played on a baize-covered table with pockets in each of the four corners and in the middle of each of the long side cushions. It is played using a cue and snooker balls: one white cue ball, 15 red balls worth one point each, and six balls of different colours: yellow (2 points), green (3), brown (4), blue (5), pink (6), black (7).