Blackball (pool) number "8" (a holdover from kelly pool), though numberless variants are not unknown. British pool tables come in 6 × 3 foot (1.8 × 0.9 m) or 7 × 3.5 ft (2.12 × 1.06 m) varieties, with 7 feet being the regulation size for league play. The table has pockets just larger than the balls and rounded, as in the game of snooker, whereas the international-style (or "American-style") table has pockets significantly wider, with pointed . Tournament rules may require the presence of more than one type of (mechanical bridge), as in snooker. There are two competing standards bodies that
Snooker who played. In 1959, Davis introduced a variation of the game known as "snooker plus" (see the "Variations" section below) to try to improve the game's popularity by adding two extra colours, but it never caught on. A major advance occurred in 1969, when David Attenborough commissioned the snooker television series "Pot Black" to demonstrate the potential of colour television with the green table and multi-coloured balls being ideal for showing off the advantages of colour broadcasting. The series became a ratings success and was for a time the second-most popular show on BBC Two. Interest in the game increased