we know billiards

Pocket billiard games are played on tables with pockets, whereas carom billiards games are played on tables that have no pockets. ... Pool refers to a set of pocket billiard games played with with one cue ball and 15 object balls on a table with six straight-edged pockets and knife-edged rails.

The word billiards refers to any of various games played on a cloth-topped, cushion-railed rectangular table by driving small, hard balls against one another or into pockets, with a long stick called a cue. Carom, or French billiards, is played with three balls, two white and one red, on a table without pockets.

The object of a game of Billiards is to score more points than your opponent, reaching the agreed amount that is needed to win the game. Like chess, it's an immensely tactical game that requires players to think both attacking and defensively at the same time.

 The word "pool" means a collective bet, or ante. Many non-billiard games, such as poker, involve a pool but it was to pocket billiards that the name became attached. The term "poolroom" now means a place where pool is played, but in the 19th century a poolroom was a betting parlor for horse racing.

Major games. There are two main varieties of billiard games: carom and pocket. The main carom billiards games are straight rail, balkline and especially three cushion billiards. All are played on a pocketless table with three balls; two cue balls and one object ball.

 Eight-Ball was invented shortly after 1900; straight pool followed in 1910. Nine-ball seems to have developed around 1920. While the term "billiards" refers to all games played on a billiard table, with or without pockets, some people take billiards to mean carom games only and use pool for pocket games.

Any game played on a table in which the object is to pocket the balls, esp snooker and pool.