There are two main types of pool table, upon which are played two quite different versions of the game.
English pool tables range in size from 6ft to 8ft, though the official tournament size is 7ft. These sizes refer to the overall length of the table from 'rail to rail'. The playing surface of the competition size table is 6ft by 3ft.
American pool tables are usually 8ft or 9ft, with the official competition size being the 9ft table. Again the size refers to the total length of the table, and the playing surface on the 9ft competition table is 8ft x 4.5ft. In bars and clubs you do sometimes find 7ft American pool tables, referred to as 'bar boxes' because of their small size.
Pool Balls & Pocket Size
The ball sets used on English pool tables comprise 7 red, 7 yellow and 1 black balls. On modern tables the reds and yellows are solid colour, with the black having an '8' in a white circle upon it. The standard size for a 6ft, 7ft or 8ft English pool table is 2 ", with pockets usually being around an inch larger to accommodate the balls.
The ball sets used on American pool tables are numbered 1-15, which are split into 'solids' and' stripes. Numbers 1-7 make up the solids, 8 is the black ball, and 9-15 the stripes. The set as standard is:
4. Purple (pink in some ball sets)
7. Brown or burgundy (tan in some ball sets)
9. Yellow and white
10. Blue and white
11. Red and white
12. Purple and white (pink and white in some ball sets)
13. Orange and white
14. Green and white
15. Brown (or burgundy) and white (tan and white in some ball sets)
The standard size for American pool balls is 2 "¼ with the pockets finished to a larger size than those on an English pool table.
Both English and American pool ball sets have a white cue ball as standard, which can feature red 'target' spots (though these are more typically seen on practice cue balls). In both English and American pool balls, Aramith (a Belgian manufacturer) are recognised as the industry leader in pool balls.
English pool tables all have napped cloth, and the current official choice is Strachan West of England wool. The cloth is available in various weights which affect the speed of play and ball behaviour.
American pool tables feature 'speedball' worsted cloth, which has not nap. This makes the cloth much faster, and combined with the larger, heavier balls changes the character of the game significantly from English pool.
The difference in table and ball size means that play on an American pool table is much faster, and potentially more technical than English pool. The larger balls mean the use of masse (high speed spin / side shots normally used in Carom billiards) is more prevalent, and in recent years it has become much more popular than the English version.
The popularity of '9 Ball' has contributed here, which is a faster version of pool played with just the balls numbered 1-9. The balls are racked in a diamond in ascending order from baulk to the bottom of the table. The aim of the game is to pot the 9, but the balls must be potted in ascending numerical order. Cannons and trick shots are allowed however, and you could get lucky and have a 'golden break'. This quick version of pool has become extremely popular in bars and clubs.