All billiard games are generally regarded to have evolved into indoor games from outdoor stick and ball games., Specific page reference needs to be filled in! The word "billiard" may have evolved from the French word billart, meaning "mace", an implement, similar to a golf club, which was the forerunner to the modern cue.

The word "pool" generally refers to pocket billiard games such as 8-ball, 9-ball, straight pool and one-pocket. The word "pool" comes from "poolrooms," where people gambled off track on horse races. They were called poolrooms as money was "pooled" to determine the odds. Because such rooms commonly provided billiard tables, pool became synonymous with billiards by association. The terms "pool" and "pocket billiards" are now interchangeable.

Equipment

Billiard balls

Other specific properties such as hardness, friction coefficient and resilience are very important. Such requirement are met today with balls cast from phenolic resin. Historically, balls were often made of clay and even elephant ivory for a period (see below for more detail). Coin-operated pool tables historically have often used either a larger ("grapefruit") or denser ("rock", typically ceramic) cue ball, such that its extra weight makes it easy to separate it from object balls (which are captured until the game ends and the table is paid again for another game) so that the cue ball can be returned for further play, should it be accidentally pocketed. Modern tables usually employ a magnetic ball of regulation or near-regulation size and weight, since players have rightly complained for many decades that the heavy and often over-sized cue balls do not "play" correctly.

Some balls used in televised pool games are colored differently to make them distinguishable on television monitors. The 4 ball used in such games is colored pink instead of purple, while the 7 ball is colored sienna (or a lighter shade of brown) rather than brown. The stripes on the 12 and 15 balls are colored the same way. Likewise, cue balls used for televised matches may depart from the norm by having spots or stripes on their surface so that spin placed on them is evident to viewers.

In snooker, there are fifteen red balls, six colored balls (yellow, green, brown, blue, pink, and black), and one white cue ball. The red balls are typically not numbered, though the six colored balls often are, and can easily be mistaken at first glace for pool balls (the design is similar, but the number does not match pool's scheme). Snooker balls are normally 2 inches (52.4 mm) in diameter.

In the carom games such as straight billiards ("straight rail"), three-cushion billiards and balkline, as well as English billiards, there are two cue balls and a red ball. One of the cue balls is typically white and the other one is either yellow or white with a red dot. These balls are normally 2 inches (69.9 mm) in diameter.

Billiard balls were originally made from ivory, imported from Africa. In the mid-19^th century, in an amazing bit of accidental environmentalism, the billiard industry realized that the supply of elephants (their primary source of ivory) was limited. They challenged inventors to come up with an alternative material that could be manufactured. John Wesley Hyatt answered the call by inventing cellulose nitrate in 1870, branded under the name celluloid, the earliest industrial plastic. Subsequently, to fix the problem of cellulose nitrate instability, the industry experimented with various other synthetic materials for billiards balls such as bakelite and other plastic compounds. Eventually phenolic resin became the industry standard and is virtually the only billiard ball material used today.

Tables

The length of the pool table will typically be a function of space, with many homeowners purchasing an 8-foot table as a compromise. High quality tables are mostly 9-footers, with a bed made of three pieces of thick slate to prevent warping and changes due to humidity. Smaller bar tables are most commonly made with a single piece of slate. Pocket billiards tables normally have six pockets, three on each side (four corner pockets, and two side pockets).

All types of tables are covered with billiard cloth (often called "felt", but actually a woven wool or wool/nylon blend called baize). Bar or tavern tables, which get a lot of play, use "slower", more durable cloth. Good quality pool cloth is "faster" (i.e. provides less friction, allowing the balls to roll farther), and the best quality pool cloth is made from worsted wool. Snooker table cloth traditionally has a nap (consistent fiber directionality) and balls behave differently when rolling against the direction of the nap. The cloth of the billiard table is typically green reflecting its origin, Specific page reference needs to be filled in! (also the reference should be added to indicate what the origin of green originally was) (and thus the name of the pool movie The Color of Money--adapted from the Walter Tevis novel of the same name--referring to the color of American currency notes).

Rack

Cues

Billiards games are played with a stick known as a cue. A cue is usually either a one piece tapered stick or a two piece stick divided in the middle by a joint of metal or phenolic resin. High quality cues are generally two pieces and are made of a hardwood, generally maple for billiards and ash for snooker.

The "butt" end of the cue is of larger circumference and is intended to be gripped by a player's hand. The "shaft" of the cue is of smaller circumference, usually tapering to an 11-14 millimeter terminus called a ferrule, where a leather tip is affixed to make final contact with balls. The leather tip, in conjunction with chalk, can be used to impart spin to the cue ball when not being hit in its center.

Cheap cues are generally one piece cues made of ramin or other low quality wood with inferior tips of various materials (usually plastic). A quality cue can be expensive and may be made of exotic woods and other expensive materials which are artfully inlaid in decorative patterns. Skilled players may use more than one cue during a game, including a separate cue for the opening break shot and another, shorter cue with a special tip for jump shots.

The mechanical bridge

Chalk

Chalk is applied to the tip of the cue stick, ideally between every shot, to increase the tip's friction coefficient so that when it impacts the cue ball on a non-center hit, no miscue (unintentional slippage between the cue tip and the struck ball) occurs. The quality of chalk varies greatly from brand to brand, which can significantly affect play. High humidity can also impair the effectiveness of chalk. Cuetip chalk is often not actually the substance typically referred to as "chalk," but some proprietary compound, frequently with a silicate base. "Chalk" may also refer to hand chalk, used to lubricate the cue and bridge hand during shooting (many players prefer talcum powder or a slick pool glove because of the long-term abrasive effect of actual carbonate chalk on the shaft of the cue).

Position play

In both carom and pocket billiards, an immensely important part of the game on each shot is the exercise of control over the final resting position of the cue ball.

In carom games an advanced player's aim on most shots is to leave the cue ball and the object balls in position such that the next shot is of a less difficult variety to make the requisite carom, and so that the next shot is in position to be manipulated in turn for yet another shot; ad infinitum.

Similarly, in many pocket billiard games, an advanced player's aim is often to manipulate the cue ball so that it is in position to pocket a chosen next ball and so that that next shot can also be manipulated for the next shot; ad infinitum. Whereas in the carom games, manipulation of the object ball's position is crucial as well, in pool this is normally not as large a factor because on a successful shot the object ball has been pocketed. Many shots in the game of one-pocket, however, have this same added object ball control factor.

If a player is not attempting to score or pocket, depending on the game, then the goal is usually to exercise control over the cue ball to leave some type of safety to make it more difficult for the opponent to score or pocket.

In order to control the cue ball on a shot, a player must master a wide variety of techniques, and have a well-founded conceptual grasp of the mechanics involved.

As stated by George Fels, 'pool's poet laureate': "The mere pocketing of a ball isn't that hard; in fact, it's relatively simple. What drives many, many players to distraction is the unpredictability of the cueball's path of travel...the game of billiards requires you to drive a ball someplace; pool, in any form, mostly asks you to stop a ball someplace. In either case, you'll fare much better when you understand the how and why of a ball's getting from one place to another." , Introduction at XVII.

Shooting techniques/mechanics

English

Sometimes english is conflated to refer as well to spin imparted on the vertical axis of the cue ball. However, an above center hit is more precisely referred to as "follow," and a below center hit, as "draw." Any time the cue ball is not struck directly in the center, some spin will be imparted, whether left or right english, follow or draw. Unintentional sidespin is a common source of missed shots. Spin is not always placed on the cue ball by the shooter; spin is naturally imparted to the cue ball from contact with pool cloth on the bed of the table and on the table's rails.

Follow

Follow, sometimes called top spin or simply "top," is spin in the direction of travel of the cue ball, such that it is spinning faster than it would from its natural roll. If the cue ball has top spin on it, it will resume rolling forward after making contact dead-on with the object ball and "follow" the object ball rather than stopping abruptly.

Top spin is imparted to a ball by hitting it above the midpoint of its vertical plane as it faces the shooter. Top spin is spin in the direction a ball naturally "wants" to take in reaction to friction from contact with the pool cloth. Because of this, a ball sliding on the cloth will rapidly pick up follow. Likewise, a ball struck so that it is spinning backwards (with draw — see below) immediately starts losing that spin, and if it travels far enough, will reach a sliding point (no spin), soon graduating to natural follow.

Follow applied to a non-dead-on shot will cause the angle of departure of the cue ball from the object ball to widen shortly after impact; the thicker the hit on the object ball, the more this effect will be noticeable (on very thin cut shots it practically does not exist). Similarly, top spin will cause a widening of the cue ball's rebound angle after impact with a rail cushion.

Follow also increases the rate of cue ball travel, both before and after object-ball impact, and actually imparts a small amount of draw to the object ball.

Draw

Draw, sometimes called back spin or "bottom," is backward spin applied to the cue ball by hitting it below the midpoint of its vertical plane as it faces the shooter. If the cue ball is hit with draw, and if that spin remains on the cue ball at the moment of impact with an object ball, the cue ball will reverse direction on a dead-on or center-to-center hit, and "draw" backwards. Draw is referred to in the United Kingdom as "screw."

Draw applied to a non-dead-on shot will cause the angle of departure of the cue ball from the object ball to narrow shortly after impact. Similarly, it will cause a narrowing of the cue ball's rebound angle after impact with a rail cushion.

Draw also slows the rate of cue ball travel, both before and after object-ball impact, and actually imparts a small amount of follow to the object ball.

Slide

Slide refers to a cue ball that is sliding across the cloth with no follow or draw spin. To illustrate this principle, if a ball was marked with a single red dot on it which faced the ceiling at the time the cue ball was struck, an observer would see the cue ball traveling with that red dot remaining fixed at the top of the ball, and observe the bottom of the ball "sliding" over the cloth.

In order to initially achieve a sliding cue ball, a middle ball hit is employed. The more speed with which the cue ball is hit in this manner, the longer the cue ball will slide before picking up natural forward roll from cloth friction. However, because of this tendency of the cue ball to acquire follow from cloth friction, in order to deliver a sliding cueball to an object ball at distance, the cue ball must be precisely hit with the necessary degree of draw so that by the time it reaches the object ball, the draw has dissipated and the cue ball is sliding at the moment of impact.

The stop and stun shots

When a sliding cue ball contacts an object ball dead-on (a center-to-center hit), the cue ball and object ball are of the same mass, and neither follow nor draw is on the cue ball at the moment of impact, the cue ball will transfer all of its momentum to the object ball and come to a complete stop. If the sliding cue ball in the preceding scenario has sidespin on it when it contacts an object ball dead on, it will come to a complete stop but spin in place at that position until the sidespin dissipates. If the cue ball and object ball contact is not dead-on but still very full, the result will often be a "stun" shot, where the cue ball departs the object ball in the expected direction but travels only a short distance. The stun effect can often be enhanced with a minimal amount of draw, to reduce cue ball speed before impact with the object ball.

The tangent line

If a cue ball is sliding at the time it contacts an object ball at an angle (i.e. a cut shot — not a center-to-center impact), the cue ball will travel in a line tangential to the point of impact between both balls--the "tangent line." Because Billiard balls are not inelastic, the resulting tangent line is slightly less than 90° from perpendicular to a line formed by the contact point between the balls.

If the cue ball hits an object ball at an angle and has follow on it, the cue ball will first travel on the tangent line and then parabolically arc forward from the tangent line in the direction of cue ball travel. By the same token, when such impact is made and the cue ball has draw on it, the cue ball will first travel on the tangent line and then parabolically arc backward from the tangent line in the opposite direction of cue ball travel. Whether follow or draw is on the cue ball, the faster the cue ball is traveling at the moment of impact, the farther it will travel on the tangent line before arcing forward or backward.

Throw

Throw refers to an object ball's motion away from the impact line due to relative sideways sliding motion between the cue ball and object ball caused by sidespin or a cut angle.

When a ball with english (sidespin) on it hits an object ball with a degree of fullness, the object ball will be "thrown" in the opposite direction of the side of the cue ball the english was applied. Thus, a cue ball with left hand english on it will "throw" a hit object ball to the right. This effect is sometimes overarchingly referred to as "the gear system;" so-called because the interaction of the cogwork gears of a clock — each circular gear is interlocked with an abutting circular gear and each spins in the opposite direction of its neighbor in a series. English on the cue ball can cause a very similar effect. If the cue ball with left hand english in the preceding scenario contacts an object ball relatively full and that object ball is frozen to another, the first object ball is thrown to the right and the second to the left, exactly as the name implies.

Throw is also imparted to a ball by collision from a cue ball with no english on it through friction. This is sometimes called "collision-induced throw." The direction of the throw depends entirely on the direction the cue ball hits the object ball from. Unlike throw cause by spin, friction from a collision induced throw "pushes" the cue ball in the same direction as the cue ball was traveling before impact. Thus, a cue ball traveling from the left will cause an impacted object ball to be thrown slightly to the left of the natural angle it would otherwise be sent.

Both varieties of throw are highly influenced by speed. Generally, the less momentum the cue ball possesses at the time of impact, the more throw will affect the object ball's resultant path of travel.

The semi-massé ("curve" or "swerve") shot

A cue ball can be made to curve in its path of travel. This is usually employed for the purpose of avoiding an interfering ball or balls. In order to achieve a curve, a player's cue stick must be elevated and the cue ball struck with english. A curve to the left is accomplished by hitting the cue ball with an elevated cue and left-hand english. A curve to the right is accomplished by hitting the cue ball with an elevated cue and right-hand english. The higher the elevation of the cue, the more steep the degree of curve. The more speed a cue ball is hit with the farther it will travel in the direction it was hit before beginning to curve.

Such shots are typically referred to as "curve shots" by North Americans and "swerve shots" by the British.

Very steep curves and even reversal of the cue ball path of direction a few moments after being struck can be accomplished by elevating the cue stick to a high degree of elevation. Such large scale curves and reversals of direction are much more difficult and are referred to as massé shots (see below).

The massé shot

Massé refers to imparting a high degree of spin along both the vertical and horizontal axes of the cue ball so that it sharply curves or even reverses direction without having to contact another ball or rail. A massé is performed by hitting the cue ball with a highly elevated cue stick (compare semi-massé). In general, the degree of the curve depends upon the distance from the center of the ball that the contact is made (the further from the center that the tip contacts the cue ball, the sooner the ball will begin to curve). The "delay" between the time that the ball is hit and the time that it starts curving is determined by the elevation of the cue butt (the more elevated it is, the more the ball curves). Massés are quite difficult and are not allowed in some venues, as the table's cloth can be easily damaged by unskilled players.

Swerve effect

Whenever a pool ball is struck with any degree of english, and with a cue that is not perfectly level, a curve results. In the two immediately-preceding sections, intentional curves of lesser and greater degrees were described. However, because in most billiards shots, the cue is slightly elevated, if english is employed, an unintentional (and imperceptible to the naked eye) curve results. This is known as "swerve" or "the swerve effect". The farther away an intended target is from the cue ball's original shooting position, the more swerve of the cue ball will affect where the cue ball arrives. For this reason, use of english (and unintentional english) are complicating factors in billiards and swerve must be compensated for. The swerve effect should not be confused with a "swerve shot," previously defined as commonwealth terminology for a curve shot.

Deflection (squirt)

Deflection can be described as displacement of the cue ball from the aimed direction in the opposite direction of the side english was applied. Like the swerve effect, deflection is an unwanted complicating factor in pool, present whenever english is employed.

The physics of deflection has been studied extensively. Basically, when english is used, the cue ball will always begin its travel in a direction not exactly as aimed; it will "squirt" off of the line parallel with the cue's direction. Deflection increases the faster the cue stick is traveling at impact and the more english has been applied.

Deflection can be decreased by the type of cue used, and at the high levels, players will often select a personal playing cue based on the amount of squirt the cue imparts (the less the better).

Because swerve and deflection (for very different reasons) each cause the cue ball to take a different path than aimed, but each does so in the opposite direction of the other, under the right conditions swerve and deflection can cancel each other out.

The jump shot

A jump shot describes any shot where the cue ball is intentionally driven into the air in a legal manner. It is not permissible in some games (e.g. Snooker) and may be frowned upon or even forbidden in some venues as attempts at it by unskilled players may cause damage to a table's cloth. A legal jump shot requires that the cue ball be hit above center, driving it down into the table, such that the ball will leave the table surface on a rebound. All authoritative rule sources deem it illegal to "scoop" under the cue ball with the tip of the cue to fling it into the air (technically because it is illegal to contact the cue ball with the ferrule of the cue, and because the cue ball is struck twice, both of which are classic fouls).

Unintentional small jumps are ubiquitous to billiards. In most billiards shots, a player's cue is slightly elevated. Whenever a ball is struck with an elevated cue, a jump, no matter how slight, occurs. An oft-used way to illustrate this principle is to lay a coin on the table approximately an inch in front of the cue ball. When shot very softly, the player will audibly hear the coin being struck and see the cue ball's reaction to that collision. When the same shot is performed with any degree of speed no sound or collision is evident, and it is clear that the coin is being jumped.

Types of games (carom and pocket)

There are two main varieties of billiard games: carom and pocket. The main carom billiards games are straight billiards, balkline and three cushion billiards. All are played on a pocketless table with three balls; two cue balls and one object ball. In all, players shoot a cue ball so that it makes contact with the opponent's cue ball as well as the object ball.

The most popular of the large variety of pocket games are 8-ball, 9-ball, one-pocket, bank pool, snooker and, among the old guard, straight pool. In 8-ball and 9-ball the object is to sink object balls until one can legally pocket the winning eponymous ball. Well-known but waning in popularity is straight pool, in which players seek to continue sinking balls, rack after rack if they can, to reach a pre-determined winning score. In both one-pocket and bank pool, the players must sink a set number of balls; respectively, all in a particular pocket, or all by banking. In snooker, players score points by alternately pocketing red balls and special balls of different colours.

Straight billiards or straight rail

In straight billiards, a player scores a point and may continue shooting each time his cue ball makes contact with both other balls.

Although a difficult and subtle game, some of the best players of straight billiards developed the skill to drive both balls into a corner and from that position were able to score a seemingly limitless number of points.

The first straight billiards professional tournament was held in 1879 where Jacob Schaefer, Sr. scored 690 points in a single turn, Specific page reference needs to be filled in! (also the reference should be added to indicate what the origin of green originally was) (that is, 690 separate strokes without a miss). With the balls barely moving and repetitively hit, there was little for the fans to watch.

Balkline

In light of these phenomenal skill developments in straight rail, the game of balkline soon developed to make it impossible for a player to keep balls in a corner for an interminable period. A balkline (not to be confused with baulk line, which pertains the game of English billiards) is a line parallel to one end of a billiard table. In the games of balkline — 18.1 and 18.2 (pronounced "eighteen-point-two") balkline, among other more obscure variations — the players have to drive either one ball or two balls (respectively) past a balkline set at 18 inches from the rail after a fixed number of shots.

Three cushion billiards

Main article: three cushion billiards

A more elegant solution was three cushion billiards, which requires a player to make contact with the other two balls on the table and contact three rail cushions in the process. This is difficult enough that even the best players can only manage to average one to two points a turn.

Eight ball

In the United States, the most commonly played game is 8-ball. On the professional scene, 8-ball players who are on the International Pool Tour are the highest paid players in the world. In the United Kingdom the game is commonly played in pubs and it is competitively played in leagues. The most prestigious tournaments including the World Open are sponsored and sanctioned by the International Pool Tour.IPT Website Rules vary widely from place to place. Pool halls in North America are increasingly settling upon the International Standardized Rules. But tavern 8-ball, typically played on smaller, coin-operated tables and in a "winner controls the table" manner, can differ significantly even between two venues in the same city. The growth of local, regional and national amateur leagues may alleviate this confusion eventually. The goal of 8-ball is to claim a suit (stripes or solids), pocket all of them, then legally pocket the 8-ball, while denying your opponent opportunities to do the same with their suit, and not sinking the 8-ball early by accident.

Nine ball

9-Ball is a rotation game where only the 1 through 9 balls and cue ball are used. The player at the table must make a legal shot on the lowest numbered ball on the table or a foul is called. The game is won by legally pocketing the nine ball (which can be done by striking the lowest numbered ball first and then driving the 9 into a pocket). 9-Ball is the predominant professional game. There are many local and regional tours and tournaments that are contested with 9-Ball. There is no particular governing body of 9-ball. Most places play with a version of "Texas Express" or WPA (World Pool Association) rules. The largest 9-ball tournaments are the independent US Open and the World 9-Ball Championships for men and women. Male professionals have a rather fragmented schedule of professional 9-Ball tournaments at this time (2005). Female professionals have a steady professional circuit that is governed by the Women's Professional Billiard Association.

One pocket

One pocket is a strategic game for two players. Each player is assigned one of the corner pockets on the table. This is the only pocket into which he can legally pocket balls. The first player to pocket the majority of the balls (8) in his pocket wins the game. The game requires far more defensive strategy than offensive strategy, much unlike 8-ball, 9-ball, or straight pool. It has been said that if 8-ball is checkers, one-pocket is chess.

Bank pool

Snooker

A pocket billiards game originated by British Officers stationed in India during the 19th century. The name of the game became generalized to also describe one of its prime strategies: to "snooker" the opposing player by causing that player to foul or leave an opening to be exploited (see Glossary of pool, billiards and snooker terms - "Snooker") .

In the United Kingdom, Snooker is by far the most popular form of billiards at the competitive level. It is played in many other countries as well. Snooker is far rarer in the U.S., where pocket billiards games such as eight ball and nine ball dominate.

List of Carom and pocket billiards games

Carom

• Eighteen-point-one balkline (18.1 balkline)
• Eighteen-point-two balkline (18.2 balkline)
• Artistic billiards
• Carambole billiards
• Four ball
• Pin billiards
• Straight rail
• Three-cushion billiards (3-cushion billiards)

Pocket

• Banks
• Bowliards
• Chicago
• Chinese Eight Ball (Chinese 8-ball)
• Cowboy
• Cribbage
• Cutthroat
• Eight ball (8-ball)
• English billiards
• Equal offense
• Internet equal offense
• Flanges
• Golf
• Indian
• Nine ball (9-ball)
• One pocket (1-pocket)
• Pin billiards variants
• Rotation
• Russian billiards
• Seven ball (7-ball)
• Six pocket (6-pocket)
• Snooker
• Straight pool
• Ten ball (10-ball)
• Three ball (3-ball)

Other variants

• Bar billiards
• Bumper pool
• Face Off
• Hexapool

Fictional variants

• Circular pool — played by the crew, and even a robot, on the starship in the film Silent Running; the table was circular, with a single pocket, in the center of the table, and played with normal pool balls. The distribution of balls at the beginning the game (e.g. rack, or some other method) was not shown. The ship had artificial gravity of course, or the balls would not have remained on the table for long.

Notable pool and billiards enthusiasts

• David Hume
• Wolfgang Amadeus Mozart
• Abraham Lincoln
• Mary, Queen of Scots
• King Louis XIV of France
• Marie Antoinette
• Mark Twain
• George Custer
• George Washington
• Napoleon Bonaparte
• Charles Dickens
• Lewis Carroll
• Thomas Jefferson
• W.C. Fields
• Jackie Gleason
• Perry Como
• Bob Hope
• Babe Ruth
• Fred Astaire
• Humphrey Bogart
• Paul Sorvino
• Jerry Orbach
• Sir Donald Bradman
• Spencer Gollan
• Immanuel Kant

More information

• Glossary of pool, billiards and snooker terms
• BCA Hall of Fame
• Pool hustling
• A Billiards category encompassing pool, snooker and carom was featured in the 2005 World Games, held in Duisburg, Germany.

References