How many types of billiards are there?

There are two main types of billiard games: carom billiardsand pocket billiards (also known as pool). Carom billiards involves hitting balls without pockets, while pocket billiards involves pocketing balls in the table's pockets. Within each category, there are numerous variations and sub-types. 

Elaboration:

• Pocket Billiards (Pool):
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  This type involves playing on a table with pockets. Popular games include eight-ball, nine-ball, straight pool, one-pocket, and bank pool. 

• Hybrid Games:
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  Some games combine elements of both carom and pocket billiards, such as American four-ball billiards, bottle pool, and English billiards

• Carom Billiards:
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  This type of billiards is played on a pocketless table with three balls (two cue balls and one object ball). Common games include straight rail, balkline, and three-cushion billiards.