Editing Snooker (section)

===Rules===
{{Main|Rules of snooker}}
[[File:Snooker table drawing 2.svg|thumb|alt=A computer-generated picture of a snooker table viewed from above, drawn exactly to scale, with the snooker balls shown in their starting positions|Illustration A: Aerial view of a [[snooker table]] with the 22 balls in their starting positions. The cue ball (white) may be placed anywhere in the [[semicircle]] (known as the "D") at the start of the game.]]

====Objective====
A player wins a frame by scoring more points than their opponent. At the start of a frame, the {{cuegloss|object balls}} are positioned on the table as shown in illustration A. Starting with the cue ball in the "D", the first player executes a {{nowrap|break-off}} shot by striking the cue ball with the tip of their cue, aiming to hit any of the red balls in the triangular {{cuegloss|pack}}. The players then take alternating {{cuegloss|turn|turns}} at playing shots,{{efn|Snooker is played either by two independent players or by more than two players taking "sides", e.g. four players constituting two sides of two players.<ref name="WPBSA_Official_Rules" />{{rp|16, 33}}}} with the aim of {{cuegloss|potting}} a red ball into a pocket and thereby scoring one point. Failure to make contact with a red ball constitutes a {{cuegloss|foul}}, which results in penalty points being awarded to the opponent.<ref name="WPBSA_Official_Rules" /> At the end of each shot, the cue ball remains in the position where it has come to rest, unless it has entered a pocket (from where it is returned to the "D"), ready for the next shot.<ref name="WPBSA_Official_Rules" />{{rp|25}} If the cue ball finishes in contact with an object ball, a {{cuegloss|touching ball}} is called;{{efn|The touching ball rule was first introduced in 1927.{{sfn|Everton|1986|page=49}}}} the player must then play away from that ball without moving it, otherwise the player will concede penalty points.<ref name="WPBSA_Official_Rules" />{{rp|23}}

When a red ball has entered a pocket, the striker{{efn|The ''striker'' is the person whose ''turn'' it is at the table, either currently in play or about to play.<ref name="WPBSA_Official_Rules" />{{rp|11}}}} must then choose a coloured ball (or "colour") and attempt to pot it.{{efn|The term ''colour'' is understood to mean one of the six remaining object balls other than red, i.e. yellow, green, brown, blue, pink and black.<ref name="WPBSA_Official_Rules" />{{rp|16}}}} If successful, the value of the potted colour is added to the player's score, and the colour is returned to its designated spot on the table.{{efn|If the colour's designated spot is obstructed by another ball and therefore not available, the colour is placed on the highest available colour spot; if no spots are available, the colour is respotted as close as possible to its own spot without touching the obstructing ball and in the direction of the top cushion.<ref name="WPBSA_Official_Rules" />{{rp|22}}}} The player must then pot another red ball followed by another colour. The process of alternately potting reds and colours continues until the striker fails to pot the desired object ball or commits a foul—at which point the opponent comes to the table to start the next turn—or when there are no red balls remaining in play.<ref name="WPBSA_Official_Rules" /> Points accumulated by potting successive object balls are called a "{{cuegloss|break}}" (see [[#Scoring|Scoring]] below).<ref name="WPBSA_Official_Rules" /> At the start of each player's turn, the objective is to first pot a red ball, unless all reds are off the table or the player has been awarded a {{cuegloss|free ball}}, which allows them to nominate another object ball in place of a red.<ref name="rule_Snoo" /> The cue ball can contact an object ball directly or it may be made to bounce off one or more cushions before hitting the required object ball.<ref name="WPBSA_Official_Rules" />{{rp|12}}

The game continues until all 15 red balls have been potted and only the six colours and the cue ball are left on the table.<ref name="WPBSA_Official_Rules" /> The colours must next be potted in the ascending order of their values, from lowest to highest, i.e. {{cuegloss|yellow}} first (worth two points), then {{cuegloss|green}} (three points), {{cuegloss|brown}} (four points), {{cuegloss|blue}} (five points), {{cuegloss|pink}} (six points), and finally {{cuegloss|black}} (seven points); at this stage of the game, each colour remains in the pocket after being potted.<ref name="WPBSA_Official_Rules" /> When the final ball is potted, the player who has accumulated the most points wins the frame.<ref name="WPBSA_Official_Rules" />{{efn|When black is the only object ball remaining on the table, the striker can claim the frame if more than seven points ahead of the opponent.<ref name="WPBSA_Official_Rules" />{{rp|10}}}} If there are not enough points remaining on the table for a player to potentially win the frame, that player may offer to concede the frame while at the table (but not while their opponent is still at the table); a frame {{cuegloss|concession}} is a common occurrence in professional snooker.<ref name="WPBSA_Official_Rules" /><ref name="rule_Snoo" /> However, players will often play on even when there are not enough points available for them to win, in the hope of laying one or more "{{cuegloss|snooker|snookers}}" to force their opponent into playing foul shots.<ref name="WPBSA_Official_Rules" /><ref name="rule_Snoo" /> Snookers are shots designed to make it difficult for the opponent to play a {{cuegloss|legal}} shot on their next turn, such as leaving another ball between the cue ball and the object ball.{{sfn|Shamos|2002|page=57}}

[[File:Snooker break.ogv|thumb|alt=|[[Computer simulation]] of a snooker {{nowrap|break-off}} shot at the start of a frame]]
If the scores are equal when all object balls have been potted, the black is used as a [[tiebreaker]] in a situation called a "{{cuegloss|re-spotted black|{{nowrap|re-spotted}} black}}". The black ball is returned to its designated spot and the cue ball is played {{cuegloss|in-hand|{{nowrap|in-hand}}}}, meaning that it may be placed anywhere on or within the lines of the "D" to start the tiebreak. The player to take the first strike in the tiebreak is chosen at random, and the game continues until one of the players either wins the frame by potting the black ball or loses the frame by committing a foul.<ref name="WPBSA_Official_Rules" />{{rp|20}}

Professional and competitive amateur matches are officiated by a referee who is charged with ensuring the proper conduct of players and making decisions "in the interests of fair play". The responsibilities of the referee include announcing the points scored during a break, determining when a foul has been committed and awarding penalty points and free balls accordingly, replacing colours onto their designated spots after being potted, restoring the balls to their previous positions after the "{{cuegloss|miss}}" rule has been invoked (see [[#Scoring|Scoring]] below), and cleaning the cue ball or any object ball upon request by the striker.<ref name="WPBSA_Official_Rules" />{{rp|40}} Another duty of the referee is to recognise and declare a stalemate when neither player is able to make any progress in the frame.<!--e.g. if the cue ball is nestled in amongst the reds, players have no option but to trade containing safeties ad infinitum--> If both players agree, the balls are returned to their starting positions (known as a "{{cuegloss|re-rack|{{nowrap|re-rack}}}}") and the frame is restarted, with the same player taking the {{nowrap|break-off}} shot as in the abandoned frame.<ref name="WPBSA_Official_Rules" />{{rp|33}} Professional players usually play the game in a sporting manner, declaring fouls they have committed that the referee has not noticed,<ref name="belf_Mark" /> acknowledging good shots from their opponent, and holding up a hand to apologise for a fortunate shot (known as a "{{cuegloss|fluke}}").<ref name="belf_Mark" />{{sfn|Peall|2017|p=64}}

====Scoring====
{| class="wikitable floatright plainrowheaders"
! scope=col | Colour
! scope=col | Value
|-
! scope=row | [[File:Snooker_ball_red.png|14px|alt=Red snooker ball|link=]] {{Cuegloss|Red}}
| 1 point
|-
! scope=row | [[File:Snooker_ball_yellow.png|14px|alt=Yellow snooker ball|link=]] {{Cuegloss|Yellow}}
| 2 points
|-
! scope=row | [[File:Snooker_ball_green.png|14px|alt=Green snooker ball|link=]] {{Cuegloss|Green}}
| 3 points
|-
! scope=row | [[File:Snooker_ball_brown.png|14px|alt=Brown snooker ball|link=]] {{Cuegloss|Brown}}
| 4 points
|-
! scope=row | [[File:Snooker_ball_blue.png|14px|alt=Blue snooker ball|link=]] {{Cuegloss|Blue}}
| 5 points
|-
! scope=row | [[File:Snooker_ball_pink.png|14px|alt=Pink snooker ball|link=]] {{Cuegloss|Pink}}
| 6 points
|-
! scope=row | [[File:Snooker_ball_black.png|14px|alt=Black snooker ball|link=]] {{Cuegloss|Black}}
| 7 points
|}

Points in snooker are gained from potting the object balls in the correct sequence. The total number of consecutive points (excluding fouls) that a player amasses during one {{Cuegloss|visit}} to the table is known as a "break".{{sfn|Shamos|2002|pp=227–228}} For example, a player could achieve a break of 15 by first potting a red followed by a black, then another red followed by a pink, before failing to pot the next red. A break of 100 points or more is referred to as a [[century break]]; these are recorded over the career of a professional player.<ref name="rise of century" /> A [[maximum break]] in snooker (often known as a "147" or a "maximum") is achieved by potting all reds with blacks, then potting all six colours in sequence, yielding 147 points.<ref name="Max 210" /> {{As of|2025|02|24}}, there have been 214 officially confirmed maximum breaks achieved in professional competition.<ref name="Official 147s" /><ref name="Max 214" />

Penalty points are awarded to a player when their opponent commits a foul. This can occur for various reasons, such as sending the cue ball into a pocket or failing to hit the object ball. The latter is a common foul committed when a player fails to escape from a "snooker", where the previous player has left the cue ball positioned such that no legal ball can be struck directly in a straight line without being wholly or partially obstructed by an illegal ball. Fouls incur a minimum of four penalty points unless a higher value object ball is involved in the foul,{{efn|An object ball is involved in a foul if it is either the nominated {{cuegloss|ball on}}, or the highest-value ball unintentionally contacted or pocketed as a result of the foul.<ref name="WPBSA_Official_Rules" />{{rp|26–29}}}} up to a maximum of seven penalty points where the black ball is concerned.<ref name="WPBSA_Official_Rules" />{{rp|26–29}}{{efn|Until the 1920s, there was no minimum penalty, and a foul on a red ball was worth one point in penalties.{{sfn|Everton|1986|pages=49–50}}}} When a foul is committed, the offending player's turn ends and the referee announces the penalty. All points scored in the break before the foul occurred are awarded to the striker, but no points are scored for any ball pocketed during the foul shot.<ref name="WPBSA_Official_Rules" />{{rp|25}}

If dissatisfied with the position left after a foul, the next player may nominate the opponent who committed the foul to continue playing from where the balls have come to rest. If the referee has also called a "miss"—meaning that the offending player is deemed not to have made their best possible attempt to hit the object ball—the next player has the option of having the balls replaced to their original positions and forcing their opponent to replay the intended shot. If, after a foul, it is not possible to cleanly strike both sides of the object ball directly, the referee may call a free ball, allowing the next player to nominate any other ball in place of the object ball they might normally have played.<ref name="WPBSA_Official_Rules" />{{rp|13, 28}} If a player is awarded a free ball with all fifteen reds still in play, they can potentially make [[Maximum break#Breaks exceeding 147|a break exceeding 147]], with the highest possible being a 155&nbsp;break, achieved by nominating the free ball as an extra red, then potting the black as the additional colour after potting the {{nowrap|free-ball}} red, followed by the fifteen reds with blacks, and finally the colours.{{sfn|Morrison|1987|p=79}} [[Jamie Cope]] was the first player to achieve a verified 155&nbsp;break during a practice frame in 2005.<ref name="guardian_murphy" />
[[File:To pot the red.jpg|thumb|upright|alt=A close-up view of a pockmarked white ball to the front and left of a red snooker ball which is itself next to a corner pocket in top right-hand corner of the image. The tip of a cue stick is visible in bottom right-hand corner of the image, about to strike the white ball.|A close-up view of a cue tip about to strike the cue ball, the aim being to pot the red ball into a corner pocket]]
One {{Cuegloss|game}} of snooker is called a "frame", and a snooker {{Cuegloss|match}} generally consists of a predetermined number of frames. Most matches in current professional tournaments are played as the best of 7, 9, or 11 frames, with finals usually the best of 17 or 19 frames. The World Championship uses a longer format, with matches ranging from the best of 19 frames in the first round to best of 35 for the final, which is played over four {{cuegloss|session|sessions}} of play held over two days.<ref name="BBCWSN1" /><!--{{fv|date=August 2024|reason=Not all of the preceding info is supported by this source.}}--> Some early world finals had much longer matches, such as the [[1947 World Snooker Championship]], which was played over the best of 145 frames.<ref name="Snooker Scene" />{{sfn|Hayton|Dee|2004|page=144}}